To furnish the ingenious youth with the means of relieving
the tediousness of a long winter's, or a wet summer's
evening,-to enable him to provide, for a party of juvenile
friends, instructive as well as recreative entertainment,
without having recourse to any of the vulgar modes of
killing time,-to qualify the hero of his little circle to
divert and astonish his friends, and, at the same time, to
improve himself, are the principal objects of the follow-
ing little Work.
The boy whose wonder and curiosity have been excited
by the experiments of the scientific lecturer, the illusions
of the ventriloquist, or the deceptions of the exhibitor of
feats of manual dexterity, will here find many of these
mysteries unveiled, and plain directions for performing them,
divested, as far as possible, of scientific or technical lan-
guage. Many of the descriptions are strictly original, and
now, for the first time, appear in print; and especial care
has been taken to introduce only such Experiments as are
adapted for performance at the parlour or drawing-room
table or fire-side, and such as are practicable without
expensive chemical or mechanical apparatus, and require
no implements beyond those which any ingenious youth
may readily furnish from his own resources, or at a
Another object of these pages is to inform, without
being dryly scientific,-by imparting interesting facts, to
stimulate the young experimentalist to inquire into the laws
that regulate them,-by aiding him to acquire dexterity
of practice, to smooth the road to the development of
principles,-and, above all, to enable him to escape an
imputation which every boy of spirit would consider the
depth of disgrace,-that of being No Conjuror !"
TILT AND BOGUB, FLBBT STRBET.
The Spectral Lamp ..................
Curious Change of Colours ............
The Protean Light .................... 2
The Chameleon Flower ................ 3
To Change the Colours of Flowers... 3
Changes of the Poppy ................... 3
To change the Colour of a Rose...... 4
Light changing White into Black ... 4
The Visibly growing Acorn............ 4
Changes in ap-Green .................. 5
To revive apparently dead Plants.... 6
Singular efot of Ters................. 5
Beauties of Crystal tion ........... 5
To rystallse Camphor ............... 7
ystalised Tin .......................... 7
Crystal in hard Water ................
Varieties of Crytals .................... 7
Heat from Cryitallsaton ............... 8
Splendid Sublimation................... 8
Artificial Ice.............................. 8
Magc Inks ............................... 8
Chameleon Liquid....................... 9
The Magic Dye ..........................
Wine changed into Water............... 10
Two colourless transparent Liquids
become black and opaque ......... 10
Two colourles Fluids make a co-
loured one .............................. 10
Change of colour by colourles
Fluids .................................... 10
Tochane a Blue Liquid to White.. 11
Veritable Bick" Tes................. I1
Restoraton of Colour by Water ...... II
The Magle Writing .................... I
Two Liqukd make a Bolid ............. IS
Two Solid sake a Liquid ............. II
A solid opaque mas made a trnu-
parent Liquid........................ IS
Two cold Liquids make a hot one ... IS
Quadruple Tuimutation ............ 1
Quintuple Trmnsmutation ............. I
Combination of Colours.................. I
Union of two Metals without heat... 13
Magi Breath ........................... 13
Two Bitter make a Sweet ............ 14
Visible and Invisible .................... 14
SIGHT AND SOUND.
Artiial Mirage........................ 1 Single Vislon with two Eyes ......... 17
option of the Eye ................ .... Two object* seen a one ............... It
Only one object can be een at a
tim e ........................................ 18
Straight objects seen crooked ......... 18
Optical llusion ........................... 19
Pin-hole Focus.............................. 19
Optical Deception ........................ 20
Accuracy of eight ........................ 20
Visual Deception........................... 21
Handwriting upon the Wall .......... 21
Imitative Haloes......................... 21
To read a Coin in the dark ............ 22
To make a Prism ........................ 22
Optical Augmentation .................. 23
Gold Fih in a glass Globe ............. 24
Colours produced by the unequal
action of Light upon the Eyes...... 24
Optical Deception ............ ......... 25
Coloured Shadows ....................... 25
Colours of Scratches ................. 25
Ocular Spectra........................... 26
Beautiful Colours of Mother of
Pearl .................... ..........
White Letters een further than
Black .......................... .......... 27
Artificial Rainbow ...................... 27
Frine about a Candle ................. 27
The Double Coloured Reflection .... 28
Luminous Cros .......................... 28
Ring of Colours round a Candle...... 28
Simple and Cheap Operaglas ....... 29
Multiplying Theatre.................... 29
Apparatus for Writing in the
Dark ........................................ 30
Portable Microcope ..................... 31
The Phenaktcope, or Stobocope... 3
To look at the Sun without injury... 33
Brilliant Water Mirror ..................
Optical illusion under Water ......... 33
The Magic Wheels....................... 34
Acoustic Bainbow ..................3...5.
Tranmission of Sound ............... 35
Progress of Sound ..................... S
Sound turning Corners.................. 37
To tell the distance of Thunder...... 38
Hearing by the Touch .................. 38
Conversation for the Deaf............... 38
Olass broken by the Voice ............ 39
Figures produced by Sound ............ 39
Transmitted Vibration ................. 40
Double Vibration ......................... 40
Champagne and Sound ............... 40
Music from Palisades ................... 41
Theory of the Jew's Harp............... 41
Music of the Snail ........................ 42
To tune a Guitar without the assit-
ance of the Bar ........................ 42
Music from Glass or Metal Rods ... 42
The Tuning-fbrk a Flute-player...... 43
Musical Bottles .................. .. 44
Theory of Whispering ................. 44
Theory of the Voie ................. 44
Sound along a Wall ................. 45
Bounds more audible by Night than
by Day .................................. 45
Musical Echo .......................... 45
Ventriloquism .......................... 4
LIQHT AND HEAT.
Flashes of Light upon revolving
Wheels ................... .......... ..... 51
Decompoeition of Light..................
lelar Refraction ................2..... 3i
Theatrical Incantations............. 58
To Imitate the Light of the Sea ...... 53
Intantaneous Lights....................... 4
To colour the Flame of a Candle .... s3
To divide the Flame of a Candle ... 55
Cane Wick Lamp ........................ 56
Camphor and Platinum Lamp......... 5
Platinum and Ether Lamp ............ M
Floating Light.......................... 57
SBbstitute for a Wax Taper............ 57
Phosphorescent Fih .................. 57
The Luminous Spectre ................. 57
Light, a Painter .......................... 5
Eect of Light upon Crystallation 58
Efect of Light on Plants .............. 58
Instantaneous Light upon Ice......... 59
White Light from Zinc................. 59
Brilliant Light from two Metals...... 59
Brilliant Light from Steel ........... 59
Lighted Tin .........................6.. 0.
Light fom Gilt Buttons ............... 60
Light from a Flower.................. 60
Light from Sugar ....................... 60
Light from the Potato ................ 61
Light from the Oyster ............... 61
Light from Derbyshire Spar ......... 61
Light from Oyster-shells ............... 62
Rings of Light in Crystal............... 62
To strike Light with Cane ............ 62
Cause of Tranparency ................ 62
Transpareny of Gld ................. 6
Tint changed by Thickness............ 63
Shadows made darker by increased
Miniature Thunder and Lightning... 64
The Burning Gla ....................... 64
Magic of Heat............................... 64
Repulsion by Heat ...................... 65
Heat passing through Glas............ 66
Metals unequally influenced by
Heat .................................... .. 66
Spontaneous Combustion ............. 67
Inequality of Heat in Fire-irons...... 67
Expansion of Metal by Heat ......... 67
Evaporation of a Metal................. 67
A Floating Metal on Fire............. 68
Heat and Cold from Flannel .......... 68
Ice melted by Air......................... 68
To hold a hot Tea-kettle on the
Hand .................................. 6
Incombustible Linen ................... U
The Burning Circle .................... U
Water of diarent Temperatures in
the smue Vessel ................... ..
Warmth of difrent Colours .......... 69
Substitute for Fire......................... 70
CAS AND STEAM.
Laughing Ga .............................. 7
The Luminous Wand ................... 74
To make Carbonic Acid Ga .......... 74
Carbonic Acid Gas in Wine or Beer
Vessels .......................... ........ 74
To extinguish Flame with Ga ...... 75
EfB ct of Hydrogen on the Voice .... 75
Magic Taper ................................ 76
The Gas Candle ..... ............. 76
Ga Bubbles .................. 76
Gae-light in the day-time............... 77
Miniature Balloons ....................... 77
Miniature Gas-lighting.................. 77
Musical Oa ............................... 78
Miniature Will o'-the-wisp ........... 79
Phosphoric Illumination ............... 19
Combustion of Iron in Oxygen GO 79
Glow-worm in Oxygen Gas............ S
Luminous Charcoal ..................... 80
Brilliant Combustion in Oxygen..... 80
Flame from Cold Metal ................ 81
Phophorus in Chlorine ............... 81
Caoutchouc Balloons .................... 8
To increase the light of Coal Gas .... 82
Gas from Indian Rubber ............... 8
Ether Gas ................................... 83
Magic Vapour ............................ 83
as from the Union of Metals......... 83
Invisible Gases made Visible ......... 84
Light under Water...... .............. 84
O eou Evanescence..................... 84
Violet-coloured as .... .................. 84
To collect Gaes ........................... 8
The Deflagrating Spoon.................. 8
What is Steam ............................ 8
The Steam Engine simplified ......... 86
To boil Water by Steam ................ 86
Distillation in Miniature ............. 87
Candle or Fire Crackers.................. 87
Steam from the Kettle .................. 87
FIRE, WATER, AND AIR.
Coloured Flames ....................
Yellow Flame....... ..................
Orange-coloured Flame ...............
emerald Green Flame.................
Instantaneous Flame ..................
The Cup of Flame....................
To cool Flame by Metal ...............
Proof that Flame is Hollow .........
Camphor sublimed by Flame.........
reen Fire ........................... ......
Brilliant Red Fire.......................
Silver Fire ........................ .....
The Fiery Fountain ....................
The Artifcial Conflagration ..........
Inflammable Powder .................
Combustion without Flame .........
Combustion of Three Metals .........
To make Paper Incombustible ......
Singular experiments with Glass
Tubes ................. ................
Aquatic Bomb ...........................
Heat not to be estimated by
Flame upon Water ....................
Roeecoloured Flame on Water.....
To set a Mixture on Fire with
W water ................................. .. 98
Waves of Fire on Water ............. 98
Explosion in Water .................... 99
Water from the Flame of a Candle... 99
Formation of Water by Fire ......... 99
Boiling upon Cold Water ............. 99
Currents in Boiling Water ............ 100
Hot Water lighter than Cold ......... 100
Expansion of Water by Cold......... 100
The Cup of Tantalus ................ 101
Imitative Diving Bell................. 101
The Water-proof Sieve................. 10
More than fill .......................... 102
To cause Wine and Water to
change places ........................ 102
Pyramid of Alum ....................... 102
Visible Vibration ....................... 10
Charcoal in Sugar .................... 104
Floating Needles ....................... 10
Water in a Sling ...................... 104
Attraction in a Glass of Water ...... 104
To prevent Cork floating In Water... 106
Instantaneous Freesing ............. 10
To frees Water with Ether ......... 105
Production of Nitre ..................... 10
Curius Transposition .................. 106
Animal Barometer ..................... 106
Magie eap .............................. 106
Equal Pressure of Water............... 107
To empty a Glass under Water...... 107
To empty a Glas of Water without
touching it........................... 107
Decompoeltion of Water............... 108
Water heavier than Wine ........... 108
To infate a Bladder without Air... 108
Air and Water Balloon.................. 108
Heated Air Balloon ............... .... 109
The Pneumatic Tinder-box ......... 109
The Bacchus Experiment ............ 109
The Mysterious Circles ............. 110
Prince Rupert's Drops................. 112
Vegetable Hygrometer................ 11
The Pneumatic Danoer ............. 11
The Ascending Snake ................. 114
The Pneumatic Phial .................. 114
Resin Bubbles ........................... 115
Moisture of the Atmosphere ......... 11
Clmates of a Room ................... 11
Babbles in Champegne .............. 116
Prooft that Air is a heavy Fluid.... 116
To support a Pea on Air ............... 11
Pyrophorus, or Air-tinder ............ 117
Beauty of a Soap-bubble ............... 118
Why a Guinea fll more quickly
than a Feather through the Air... 119
Solidity of Air ............................ 120
Breathing and Smelling ............. 120
SLEIGHTS AND SUBTLETIES.
The Ring and the Handkerchief.... 125
The Knotted Handkerchief ......... 126
The Invisible Springs .................. 128
The Miraculous Apple.................. 129
The Self-balanced Pall.................. 130
The Phantom at command ........ 130
The Miraculous Shilling............... 132
The Locomotive Shilling............... 133
The Penetrative Sixpence ............ 134
The Vanishing Sixpence.............. 134
To make a Sixpence balance and spin
on Its edge on the point of a Needle 135
The Multiplying Coin .............. 135
The Wonderful Hat ................... 136
To bring a Person down upon a
The Apparent Impossibility........... 137
An Omelet Cooked in a Hat over
the Flame of a Candle .............. 137
The Impossible Omelet .............. 138
Go If you can.............................. 138
The Figure Pussle ..................... 138
The Visible Invisible .................. 18
The Double Meaning.................. 139
Quite tired out........................ 19
Something out of the Common ...... 19
To rub one Sixpence into two ....... 140
Magic Circle .............................. 140
The Forcing Peat........................ 141
The Nerve Feat ......................... 143
The Turn-over Feat.................... 144
To tell the Name of a Card
thought of ............................. 144
A Card thought of by one Person, to
be found in a part of the Pack
named by another Person.......... 145
To tell the Names of the Cards by
the Weight ........................... 146
The Queens going to dig for
Diamonds ........................ ... 148
The Card in the Egg ................ 149
The Ingenious Confederacy ......... 15
The Changeable Cards ................ 1
"Hold it Fastl ......................... 157
Illusions of Touch ...................... 161
Illusion of the Taste ................... 162
The General Blecher ................. 162
Influence of colored Glss on
bulbous Roots ........................... 16
The Spinning-top "sleep" ......... 163
To Judge of.Weights .................... 164
Quicksilver and Oil united............ 164
To dissolve the Bods In Glss......... 164
Waterproof Paper........................ 165
To dissolve Gold or Platinum ....... 165
Colder than Ice .......................... 165
Contrcrystlltion ................... 165
One and one do not make two ...... 166
To copy Writing instantly.............. 166
The Rival Dials ......................... 166
To spin Indian Rubber .............. 1M
Indelible Writing .................... 167
Vegetable Anatomy..................... 167
To tell what o'Clock It is by the
Moon ................................. 168
The Physiognotype ..................... 169
Infinite Divisibilty of Matter ....... 19
Holding the Breath .................... 170
Sand In the Hour-Gla ............... 170
Resistance of nd ..................... 171
Glass broken by Band ................. 172
To bleach Ivory........................... 17
Vanishing Shells ....................... 17
The Magic Egg .......................... 172
The Masc Whirlpool .................. 17
Magic Porelain....................... 17
A Galvanic Tongue ................... 176
Drinking Porter out of Pewter ...... 176
Electric or Galvanic Preservation.. 176
Light from the Diamond............... 177
To break a Stone with a blow of
the Fi t ............................... 177
Mimic rost-work ................... 177
To melt Lead in a piece of Paper... 178
Hydrostatle Balance ................... 178
Metallic Reduction .................... 179
Electrical Attraction and Re-
pulsion ................................ 179
Alchemical Electricity................. 180
The Electric Balls....................... 181
The Electric Dance .................... 181
Electric Light............................. 181
Electric Light from Brown Paper... 181
Sudden Production of Light ......... 181
Electricity of the Cat ................. 18
THE SPECTRAL LAMP.
Aix some common salt with spirit of wine in a
platinum or metallic cup; set the cup upon
a wire frame over a spirit-lamp, which should
be inclosed on each side, or in a dark-lan-
tern: when the cup becomes heated, and the
spirit ignited, it will burn with a strong yellow
Sflame; if, however, it should not be perfectly
yellow, throw more salt into the cup. The lamp being thus pre-
pared, all other lights should be extinguished, and the yellow
lamp introduced, when an appalling change will be exhibited;
all the objects in the room will be but of one colour, and the com-
plexions of the several persons, whether old or young, fair or
brunette, will be metamorphosed to a ghastly, death-like, yellow;
whilst the gayest dresses, as the brightest crimson, the choicest
lilac, the most vivid blue or green-all will be changed into
one monotony of yellow: each person will be inclined to laugh
at his neighbour, himself insensible of being one of the spectral
Their astonishment may be heightened by removing the yellow
light to one end of the room, and restoring the usual or white light
at the other; when one side of each peron's dress will resume
its original colour, while the other will remain yellow; one cheek
may bear the bloom of health, and the other, the yellow of jaundice.
Or if, when the yellow light only is burning, the white light be
introduced within a wire sieve, the company and the objects in the
apartment will appear yellow, mottled with white.
Red light may be produced by mixing with the spirit in the cup
over the lamp, salt of strontian instead of common salt; and the
effect of the white or yellow lights, if introduced through a sieve
upon the red light, will be even more striking than the white upon
the yellow light.
CURIOUS CHANGE OF COLOURS.
Let there be no other light than a taper in the room; then put
on a pair of dark green spectacles, and having closed one eye, view
the taper with the other. Suddenly remove the spectacles, and
the taper will assume a bright red appearance; but, if the specta-
eles be instantly replaced, the eye will be unable to ditinguish
any thing for a second or two. The order of colours will, therefore,
be as follows:-green, red, green, black.
THE PROTEAN LIGHT.
Soak a cotton wick in a strong solution of alt and water, dry it
place it in a spirit-lamp, and, when lit, it will give a bright yellow
light for a long time. If you look through a piece of blue glass at
the flame, it will lose all its yellow light, and you will only per-
ceive feeble violet rays. If, before the blue gls, you place a pale
yellow glass, the lamp will be absolutely invisible, though a candle
may be distinctly een through the same glase.
THB CHAMELEON LOWERS.
Trim a spirit-lamp, add a little salt to the wick, and light it.
Set near it a scarlet geranium, and the Bower will appear yellow.
Purple colours, in the same light, appear blue.
TO CHAOE THE COLOURS O FLOWEzS.
Hold over a lighted match, a purple columbine, or a blue
larkspur, and it will change first to pink, and then to black. The
yellow of other lowers, held a above, will continue unchanged.
Thus, the purple tint will instantly disappear from a heart'-ease,
but the yellow will remain; and the yellow of a wall-lower will
continue the same, though the brown streak will be discharged.
If a carpet, crimson, or maroon dahlia be tried, the colour will
change to yellow; a fact known to gardeners, who, by this mode,
variegate their growing dahlias.
CHANGES 01 THR POPPY.
Some lowers, which are red, become blue by merely bruising
them. Thus, if the petals of the common corn-poppy be rubbed
upon white paper, they will stain it purple, which may be made
green by washing it over with a strong solution of potash in water.
Put poppy petals into very dilute muriatic acid, and the infusion
will be of a foid red colour; by adding a little chalk, it will
become of the olour of port wine; and this tint, by the addition
of potash, may be changed to green or yellow.
TO CHANGE THE COLOUR Of A 20R3.
Hold a red rose over the blue lame of a common match, aad
the colour will be discharged wherever the fame touches the leaves
of the lower, so a to render it beautifuly variegated, or entirely
white. If it be then dipped into water, the redness, after a time,
will be restored.
LIGHT CHANGING WHITE INTO BLACK.
Write upon linen with permanent ink (which is a strong
solution of nitrate of silver), and the characters will be scarcely
visible; removedhe linen into a dark room, and they will not
change; but expose them to a strong light, and they will be inde-
THE VISIBLY OROWING ACORN.
Cut a circular piece of card to fit the top of a hyacinth glass,
o as to ret upon the ledge, and exclude the air. Pierce a hole
through the centre of the card, and pas
through it a strong thread, having a small
piece of wood tied to one end, which, rest-
ing transversely on the card, prevents its
being drawn through. To the other end of
the thread attach an acorn; and, having
half filled the glass with water, spend
the scorn at a sort distance from the
The glass must be kept in a warm
room; and, in a few days the team
which has generated in the glass wl
hang from the acorn in a large drop.
shortly afterward, the sem wll btM,
the root will protude sad thrust itelf ite
he water; ad, in a few days more, a tm will sheet at the
other d, and, rising upwards, will press against the ard, in
which an orifice mnt be made to allow it to pa through. From
this stem, small leaves will oon be observed to sprout; and, in
the ourse of a few weeks, you will have a handsome oak plant,
several inches in height.
CHANGES IN IAP OGEEN.
Sap green is the inspissated juice of the buckthorn berries: if
a little carbonate of soda be dropped into it, the colour will be
changed from green to yellow; it may be reddened by aids, and
its green colour restored by chalk.
TO IREIVE APPARENTLY DBAD PLANTS.
Make a strong solution of camphor in spirit of wine, which
add to soft water, in the proportion of a dram to a pint. If
withered, or apparently dead plants be put into this liquid, and
allowed to remain therein from two to three hour, they will
SINGULLAB ErlICT 0 TEA*.
If tea are dropped on a dry piece of paper, stained with the
juice of the petals of mallows or violets, they will change the paper
to a permanently green colour,
BEAUTIXI 01 CRYTTALLITATION.
Disolve alum in hot water until no more can e dissolved in
it; place in it a smooth glass rod and a stick of the same sim;
naEt dy, the stick will be found covered with erytal, but the
glass rd will be fee from them: in this case, the crystals ling to
the rough suroe of the stick, but have no hold upon the smooth
surface of the glass rod. But if the rod be roughened with a fil
at certain intervals, and then placed in the alum and water, the
crystals will adhere to the rough surfaces, and leave the smooth
bright and clear.
Tie some threads of lamp-cotton irregularly around a copper
wire or glass rod; place it in a hot solution of blue vitriol, strong
as above, and the threads will be covered with beautiful blue
crystals, while the glass rod will be bare.
Bore a hole through a piece of coke, and suspend it by a
string from a stick, placed across a hot solution of alum; it will
float; but, as it becomes loaded with crystals, it will sink in the
solution according to the length of the string. Gas-coke has
mostly a smooth, shining, and almost metallic surface, which the
crystals will avoid, while they will cling only to the most irregular
and porous parts.
If powdered turmeric be added to the hot solution of alum, the
crystals will be of a bright yellow; litmus will cause them to bI
of a bright red; logwood will yield purple; and common writing
ink, black; and the more muddy the solution, the finer will be
Tokeep coloured alum crystals from breaking, or losing their
colour, place them under a glass shade with a saucer of water;
this will preserve the atmosphere moist, and prevent the crystals
getting too dry.
If crystals be formed on wire, they will be liable to break a
from the expansion and contraction of the wire by changes of
TO CYSTALLUI CAMUHOL.
Dissolve camphor n pirit of wine, moderately heated, until the
spirit will not dissolve any more; pour some of the solution into
a old glass, and the camphor will instantly cryalli in beautify
tree-like form, such as we ee in the show-glasses of camphor in
Mix half an ounce of nitric acid, ix dram of muriatic acid,
and two ounces of water; pour the mixture upon a piece of tin
plate previously made hot, and, after washing it in the mixture, it
wil bear a beutitl crystalline surfce, in feathery frms. Thi
is the celebrated swd meellque, and, when varnished, is made
Into ornamental boxes, &c. The figure will vary according to the
degree of hat previously given to the metal.
CTYSTALI IN HARD WATUL
Hold in a wine-glass of hard water, a crystal of oxalic acd,
and white thread will instantly descend through the liquid, -
pended from the crystal
VARIXTIRS OF CITYTALS.
Make distinct solutions of common sult, nitre, and alum; set
them in three saucer in any warm place, and let part of the water
dry away or evaporate; then remove them to a warm room. The
particle of the salts in each aucer will begin to attract each
other, and form crytals, but not all of the me figure: the
common salt will yield crystals with six square and equal fhes,
or ides; the nitr, six-sided crystals; and the alum, eightided
rystal; and if these crystals be disolved over and over again,
they wi always appear in the same forms.
HEAT rEOM CRYSTALLISATION.
Make a strong solution of Epsom salt in hot water, and while
warm, bottle it, cork it closely, and it will remain liquid; draw out
the cork, when the salts will immediately crystallise, and, in the
proes, the remaining liquid and the bottle will become very
Put into a fask a small portion of iodine; hold the flnk over
the flame of a spirit-lamp, and, from the state of rich ruby crystals,
the iodine, on being heated, will become a ruby-coloured trans-
parent gas; but, in cooling, will resume its crystalline form.
Mix four ounces of nitrate of ammonia, and four ounce of
subcarbonate of soda, with four ounces of water, in a tin vessel,
and in three hours the mixture will produce ten ounce of ice.
Dissolve oxide of cobalt in acetic acid, to which add a little
nitre; write with this solution; hold the writing to the fre, and it
will be of a pale rose colour, which will disappear on cooling.
Dissolve equal parts of sulphate of copper and muriate o
anmmnia in water; write with the solution, and it will give yellow
colour when heated, which will disappear when cold.
Dissolve nitrate of bismuth in water; write with the solution,
and the characters will be invisible when dry, but will become
legible on immersion in water.
Dissolve, in water, muriate of cobalt, which is of a bluish-green
colour, and the solution will be pink; write with it, and the
characters will be scarcely visible; but, if gently heated, they will
appear in brilliant green, which will disappear as the paper cools.
Put a small portion of the compound called mineral chameleon
into several glasses, pour upon each water at different tempera-
tures, and the contents of each glass will exhibit a different shade
of colour. A very hot solution will be of a beautiful green colour;
a cold one, a deep purple.
Make a colourless solution of sulphate of copper; add to it a
little ammonia, equally colourless, and the mixture will be of an
intense blue colour; add to it a little sulphuric acid, and the blue
colour will disappear; pour in a little solution of caustic ammonia,
and the blue colour will be restored. Thus may the liquor be
thrice changed at pleasure.
THE MAGIC DYES.
Dissolve indigo in diluted sulphuric acid, and add to it an
equal quantity of solution of carbonate of potass. If a piece of
white cloth be dipped in the mixture, it will be changed to blue;
yellow cloth, in the same mixture, may be changed to green; red
to purple, and blue litmus paper to red.
Nearly fill a wine-glass with the juice of beet-root, which is
of a deep red colour; add a little lime water, and the mixture will
be colourless; dip into it a piece of white cloth, dry it rapidly, and
in a few hours the cloth will become red.
WINE CHAOGED INTO WATRL
Mix a little solution of mbacetate of lead with port wine;
filter the mixture through blotting paper, and a colorless liquid
will pa through; to this add a mall quantity of dry salt of tartar,
when a spirit will rise, which may be inflamed on the surface of
TWO COLOURLISS TRANSPARENT LIQUIDS BECOME BLACK
Have in one vessel some sulphuric acid, and in another an
infusion of nut-galls; they are both colourless and transparent;
mix them, and they will become black and opaque.
TWO COLOURLISS FLUIDS MAKX A COLOURED ONE.
Put into a wine-glass of water, a few drops of prussite of
potash; and into a second glass of water, a little weak solution of
sulphate of iron in water: pour the colourles mixtures together
into a tumbler, and they will be immediately changed to a bright
deep blue colour.
Or, mix the solution of prussite of potash with that of nitrate
of bismuth, and a yellow will be the product.
Or, mix the solution of prusiate ofpotash with that of sulphate
of copper, and the mixture will be of a reddish brown colour.
CHAMNO 01 COLOUK BT COLOURI.ES FLUIDS.
Three different colours may be produced from the same in-
fuaion, merely by the addition of three colourles fluids Slie
a little red cabbage, pour boiling water upon it, and when old,
decant the dear infiuion, which divide into three wine-glsse:
to one, add a mall quantity of solution of alum in water; to the
second, a little solution of potash in water; and to the third, a few
drops of muriatic acid. The liquor in the first glass will assume a
purple colour, the second, a bright green, and the third, a rich
Put a dram of powdered nitrate of cobalt into a phial containing
an ounce of the solution of caustic potas ; cork the phial, and the
liquid will assume a blue colour, next a lilac, afterwards a peach
colour, and lastly a light red.
TO CHANGE A BLUE LIQUID TO WHITE.
Dissolve a small lump of indigo in sulphuric acid, by the aid
of moderate heat, and you will obtain an intense blue colour; add
a drop of this to half a pint of water, so as to dilute the blue;
then pour some of it into strong chloride of lime, and the blue will
be bleached with almost magical velocity.
VIRITABLE BLACK" TEA.
Make a cup of strong green tea; dissolve a little green cop-
peras in water, which add to the tea, and its colour will be black.
RESTORATION OF COLOUR BT WATER.
Water being a colourless fluid, ought, one would imagine, when
mixed with other substances of no decided colour, to produce a
colourless compound. Nevertheless, it is to water only that blue
vitriol,' or sulphate of copper, owes its vivid blueness, as will be
plainly evinced by the following simple experiment. Heat a few
crystals of the vitriol in a fire shovel, pulverize them, and the
powder will be of a dull and dirty white appearance. Pour a little
water upon this, when a slight hissing noise will be heard, and at
the same moment, the blue colour will instantly re-appear.
Under the microscope, the beauty of this experiment will be
increased, for the instant that a drop of water is placed in contact
I1 TIAMn UTATION1.
with t vitriol, te powder may be see to sboot into ble prim.
If a crytal e pruit of potah be imiarly heated, ite yeow
colour will vanuh, but re-appear on being dropped into water.
TRE MAGIC WRITINO.
Dissolve a small portion of green-copperas in water, and soak
in it sheets of writing paper, so a to allow them to be taken out
whole, and then dried; then, cover the paper with very finely
powdered galls, and write on it with a pen dipped in water; when
dry, brush 'the ll, and the writing will appear.
TWO LIQUIDS MAKE A SOLID.
Dissolve mriate of lime in water until it will disolve no more;
make alo a similar solution of carbonate of potash; both will be
transparent fluids; but if equal quantities of each be mixed and
stirred together, they will become a solid mass.
TWO SOLIDS MAKE A LIQUID.
Rub together in a mortar, equal quantities of the crystals of
Gluber's saltand nitrate of ammonia, and the two salts will slowly
become a liquid.
A SOID OPAQUE MAiS MADS A TRANSPARENT LIQUID.
Take the solid mixture of the solutions of muriate of lime and
carbonate of potash, pour upon it a very little nitric acid, and the
solid opaque mas will be changed to a transparent liquid.
TWO COLD LIQUIDS MAKE A NOT ONl.
Mix tour drama of ulphuric acid (oil of vitriol), with oe
dam of cold water, suddenly, in a eup, and the mixture will be
nearly half a hot again as boiling water.
Dissolve a small piece of nickel in nitric acid, and it will
appear of a fine gras-green colour; add to it a little ammonia,
and a blue precipitate will be formed; this will change to a purple-
red in a few hours, and the addition of any acid will convert it to
Heat potassium over the flame of a spirit-lamp, and the colour
will change from white to a bright azure, thence to a bright blue,
green, and olive.
COMBINATION OF COLOURS.
Cut out a disk or circle of pasteboard, and cover it with paper
half green and half black: cause the disk to be rapidly turned
round (like the shafts of a toy windmill,) and the colours will
combine and produce white.
UNION OF TWO METALS WITHOUT HEAT.
Cut a circular piece of gold leaf, called, "dentist's gold," about
half an inch in diameter; drop upon it a globule of mercury, about
the size of a small pea, and if they be left for a short time, the
gold will lose its solidity and yellow colour, and the mercury its
liquid form, making a soft mass of the colour of mercury.
Half fill a glass tumbler with lime water; breathe into it
frequently, at the same time stirring it with a piece of glass. The
fluid, which before was perfectly transparent, will presently become
quite white, and, if allowed to remain at rest, real chalk will be
TWO nITTEZ MAKE A SWIZT.
It has been discovered, that a mixture of nitrate of silver
with hypo-nlphate of soda, both of which ae remarkably bitter,
will produce the sweetest known substance.
VISIBLE AND INVISILI,.
Write with French chalk on a looking glass; wipe it with a
handkerchief and the line will disappear; breathe on it, and
they will re-appear. This alternation will take place for a great
number of times, and after the lapse of a considerable period.
SIGHT & SOUND*
aau mirage is an optical phenomenon, produced
by the refactive power of the atmosphere.
The appearance presented is that of the double
imge of an object in the ir; one of the immgen
being in the natural position, and the other in-
verted, so a to resemble a natural object and
its image in the water. The mirage i com-
monly vertical, or upright, that i, presenting the appearance,
above described, of one object over another, like a ship above
its shadow in the water. Sometimes, however, the image is
horizontal, or upon the water, and at other times, it is seen on
the right or lefthand of the real object, or on both aide.
All the effect of the mirage may be represented artifially
to the eye. For this purpose, provide a gta tumbler two-thirds
t of water, and pour spirit of wine upon it; or pour into a
tumbler some yrup, and in it up with water: a the water and
93CHIF3 AKE) Z O ND.
BIGHT AND SOUND.
spirit, or the syrup and water incorporate, they will produce a
reactive power; then, by looking through the mixed or inter-
mediate liquids at any objet held behind the tumbler, its inverted
image may be seen. The same effect, Dr. Wollaston has shown,
may be produced by looking along the side of a red-hot poker at a
word or object ten or twelve feet distant. At a distance les than
three-eighths of an inch from the line of the poker, an inverted
image was seen; and within and without that, an erect image.
The above phenomena may likewise be illustrated, by holding
a heated iron above a tumbler of water, until the whole becomes
changed; then withdraw the iron, and, through the water, the
phenomena of the mirage may be seen in the finest manner.
Or, look directly above the footlights of the stage of a theatre,
the lame of a candle, or over the glas of a lighted lamp, and a tre-
mulous motion may be observed; because the warm air rise, and its
reacting power being leh than that of the colder air, the current
are rendered visible by the distortion of objects viewed through
them. The ame effect is observable over chimney pots, and
lated roof which have been heated by the amn.
MOTION OW THi ITI.
On entering a room, we imagine that we see the whole side
of it at once, as the cornice, the pattern of the paper-hanging,
pictures, chair, &c., but we are deceived; for each object is rapidly,
but singly presented to the eye, by its constant motion. If the
eye were steady, vision would be lost. For example, fix the eye
on one point, and you will find the whole scene become more and
more obscure, till it vanihes. Then, if you change the direction
of the eye ver o little, at once the whole scene will be again
perfect before you
SIGHT AND SOUND.
SINGLE VISION WITH TWO EYES.
As we have two eyes, and a separate image of every external
object is formed in each, it may be asked, Why do we not see
double? The answer is, It is a matter of habit. Habit alone
teaches us, that the sensations of sight correspond to anything
external, and shews to what they correspond. Thus, place a wafer
on a table before you; direct your eyes to it, that is, bring its image
on both retinae to those parts which habit has ascertained to be the
most sensible, and best situated for seeing distinctly, and you will
see only the single wafer. But, while looking at the wafer, squeeze
the upper part of one eye downwards, by pressing on the eyelid
with the finger, and thereby forcibly throw the image on another
part of the retina of that eye, and double vision will be immediately
produced; that is, two wafers will be distinctly seen, which will
appear to recede from each other as the pressure is stronger, and
approach, and finally blend into one, as it is relieved. The same
effect may be produced without pressure, by directing the eyes to
a point nearer to, or farther from them, than the wafer; the optic
axes, in this case, being both directed away from the object seen.
TWO OBJECTS SEEN AS ONE.
On a sheet of black paper, or other dark ground, place two
white wafers, having their centres three inches distant. Vertically
above the paper, and to the left, look with the right eye, at twelve
inches from it, and so that, when looking down on it, the line
joining the two eyes shall be parallel to that joining the centre of
the wafers. In this situation, close the left eye, and look full with
the right perpendicularly at the wafer below it, when this wafer
only will be seen, the other being completely invisible. But, if it
be removed ever so little from its place, either to the right or left,
SIGHT AND ONOD.
above or below, it will become immediately visible, and start, as it
were, into existence. The distances here set down may, perhaps,
vary slightly in different eyes.
Upon this curious effect, Sir John Herschel observes: It will
cease to be thought singular, that this fact of the absolute invisi-
bility of objects in a certain point of the field of view of each eye,
should be one of which not one person in ten thousand is apprised,
when we learn, that it is no( extremely uncommon to find persons
who have for some time been totally blind with one eye, without
being aware of the fact."
ONLY ONE OBJECT CAN BE SEEN AT A TIME.
Look at the pattern of the paper-hanging of a room, a picture,
or almost any other object in it; then, without altering your position,
call to mind the magnificent dome of St. Paul's Cathedral; the
pattern of the paper-hanging, or the subject of the picture, though
actually impressed on the retina of the eye, will be momentarily
lost sight of by the mind; and, during the instant, the recollected
image of the dome rising from the dingy roofs of London, will be
distinctly seen, but in indistinct colouring and outline. When
the object of the recollection is answered, the dome will quickly
disappear, and the paper-hanging pattern, or the picture, again
resume the ascendancy.
STRAIGHT OBJECTS SEEN CROOKED.
Look through a series of vertical bars, as those of a palisade, or
of a Venetian window-blind, at the wheel of a carriage passing
along the street, and the spokes of the wheel, instead of appearing
straight, as they naturally would do, if no bar intervened, seem to
SIGHT AND SOUND.
be of a curved form. The velocity of the wheel must not be so
great as to prevent the eye from following the spokes as they
Again, when the disk of the wheel, instead of being marked by
a number of radiant lines, has only one radius marked upon it, it
presents the appearance, when rolled behind the bars, of a number
of radii, each having the curvature corresponding to its situation,
their number being the same as that of the bars through which you
look at the wheel. It is, therefore, evident that the several por-
tions of one and the same line, seen through the intervals of the
bars, form, on the retina of the eye, so many different radii.
Shut one eye, direct the other to any fixed point, as the head
of a pin, and you will indistinctly see all other objects. Suppose
one of these to be a strip of white paper, or a pen lying upon a
table covered with a green cloth: either of them will disappear
altogether, as if taken off the table; for the impression of the green
cloth will entirely extend itself over that part of the retina which
the image of the pen occupied. The vanished pen will, however,
shortly re-appear, and again vanish; and the same effect will take
place when both eyes are open, though not so readily as with one
Make a pin-hole in a card, which hold between a candle and a
piece of white paper, in a dark room, when an exact representation
of the flame, but inverted, will be seen depicted upon the paper,
and be enlarged as the paper is drawn from the hole; and if, in a
20 SIGHT AND SOUND.
dark room, a white screen or sheet of paper be extended at a few
feet from a small round hole, an exact picture of all external objects,
of their natural colours and forms, will be seen traced on the screen;
moving objects being represented in motion, and stationary ones
Prick a hole in a card with a needle; place the same needle
near the eye, in a line with the card-hole, look by daylight at the
end of the needle, and it will appear to be behind the card, and
Prick a hole with a pin in a black card, place it very near the
eye, look through it at any small object, and it will appear larger
as it is nearer the eye; while, if we observe it without the card,
it will appear sensibly of the same magnitude at all parts of the
ACCURACY OF SIGHT.
Rule a short line upon a slate, and upon another slate, rule
another line, one-eleventh longer than the first: a person possessing
what is called "a true eye," may perceive the difference in length,
even though fifty or sixty seconds elapse between looking at the
first and the second lines. If they differ only one-twentieth, then
an interval of thirty-five seconds may elapse without destroying the
judgment; but, if it be longer, the estimate will be incorrect
When the difference between the lines amounts only to one-fiftieth,
an interval of three seconds between the examination of each, is
the longest that can be allowed without interfering with the cor-
rectness of the comparison.
BIGHT AND SOUND.
Let a room be only lit by the feeble gleam of a fire, almost
extinguished, and the eye will see with difficulty the objects in
the apartment, from the small degree of light with which they
happen to be illuminated. The more exertion is made to ascertain
what these objects are, as by fixing the eye more steadily upon them,
the greater will be the difficulty in accomplishing it. The eye will
be painfully agitated, the object will swell and contract, and partly
disappear, but will again become visible when the eye has recovered
from its delirium.
HAND-WRITING UPON THE WALL.
Cut the word or words to be shewn, out of a thick card or
pasteboard, place it before a lighted lamp, and the writing will be
distinctly seen upon the wall of the apartment.
Look at a candle, or any other luminous body, through a plate
of glass, covered with vapour, or dustin a finely divided state, and
it will be surrounded with a ring of colours, like a halo round the
sun or moon. These rings increase with the size of the particles
which produce them; and their brilliancy and number depend on
the uniform size of these particles.
Or, haloes maybe imitated bycrystalizingvarious salts upon thin
plates of glass, and looking through the plate at a candle or the sun.
For example, spread a few drops of a strong solution of alum
over a plate of glass so as to crystalize quickly, and cover it with a
epuat scrcely visible to the eye. Then place the eye close behind
SIGHT AND SOUND.
the smooth side of the glass plate, look through it at a candle, and
you will perceive three fine haloes at different distances, encircling
TO READ A COIN IN THE DARK.
By the following simple method, the legend or inscription upon
a coin may he read in absolute darkness. Polish the surface of
any silver coin as highly as possible; touch the raised parts with
aqua-fortis, so as to make them rough, taking care that the parts
not raised retain their polish. Place the coin thus prepared upon
red-hot iron, remove it into a dark room, and the figure and
inscription will become more luminous than the rest, and may be
distinctly seen and read by the spectator. If the lower parts of the
coin be roughened with the acid, and the raised parts be polished,
the effect will be reversed, and the figure and inscription will appear
dark, or black upon a light or white ground.
This experiment will be more surprising if made with an old
coin, from which the figure and inscription have been obliterated;
for when the coin is placed upon the red-hot iron, the figure and
inscription may be distinctly read upon a surface which had hitherto
This experiment may be made with small coins upon a heated
poker, a flat-iron, or a salamander. The effect will be more perfect
if the red-hot iron be concealed from the eye of the spectator: this
may be done by placing upon the iron a piece of blackened tin,
with a hole cut out, the size of the coin to be heated.
TO MAKE A PRISM.
Provide two small pieces of window-glass and a lump of wax;
soften and mould the wax, stick the two pieces of glass upon it,
so that they meet, as in the cut, where w is the wax, g and g
SIGHT AND BOUND.
the glass stuck to it (Mg. 1). The end view (Fg. 2) will
ig..L ris.. shew the angle, a, at which the
l pieces of glass meet; into which
angle put a drop of ter.
To use the iimument thus made,
make a small hole, or a narrow
horizontal slit, so that yo can see the sky through it, when you
stand at se distance from it in the room: or a piece of paste-
board placed in the upper part of the window-sash, with a slit
cut in it, will serve the purpose of the hole in the shutter. The
slit should be about one-tenth of an inch wide, and an inch or
two long, with even edges. Then hold the prism in your hand,
place it close to your eye, and look through the drop of water, when
you will see a beautiful train of colours, called a spectrum; at one
end red, at the other violet, and in the middle yellowish green.
The annexed figure 3 will better explain the direction in which
is. s to look: here, e, is the eye of
A the spectator, p, is the prism,
A /, the hole in the shutter or
pasteboard, a, the spectrum.
By a little practice, you will
C soon become accustomed to
look in the right direction, and.
will see the colours very bright
I and distinct.
By means of this simple contrivance, white light may be
analysed, and proved to consist of coloured rays, and several of
its properties be beautifully illustrated.
Take a glass rummer that is narrow at bottom and wide at top,
into which put a half-sovereign, and fill the glass three-fourths
BIGHT AND SOUND.
with water; place on it a piece of paper, and then a plate, and
turn the glass upside down quickly, that the water may not escape:
by looking sideways at the glass, yon will perceive a sovereign at
the bottom, and, higher up, the half-sovereign floating near the
nsrface. Fill the glass with water, and the large piece only will
GOLD FISH IN A OLASS GLOBE.
A single gold fish in a globe vase, is often mistaken for two
fishes, because it is seen as well by the light bent through the
upper surface of the water, as by straight rays passing through the
side of the vase.
COLOURS PRODUCED BY THE UNEQUAL ACTION OF LIGHT
UPON THE EYES.
If we hold a slip of white paper vertically, about a foot from the
eye, and direct both eyes to an object at some distance beyond it,
so as to see the slip of paper double, then, when a candle is brought
near the right eye, so as to act strongly upon it, while the left eye
is protected from its light, the left-hand slip of paper will be of a
tolerably bright green colour, while the right-hand slip of paper,
seen by the left eye, will be of a red colour. If the one image
overlaps the other, the colour of the overlapping parts will be white,
arising from a mixture of the complementary red and green. When
equal candles are held equally near to each eye, each of the images
of the slip of paper is white. If when the paper is seen red and
green by holding the candle to the right eye, we quickly take it to
the left eye, we shall find that the left image of the slip of paper
gradually changes from green to red and the right one from red
to greens, both of them having the same tint during the time that
the change is going on.
SIGfT AND SOUND.
Look steadily at a carpet having figures of one colour, green,
for example, upon a ground of another colour, suppose red, and
you will sometimes see the whole of the green pattern as if the
red one were obliterated; and at other times, you will see the whole
of the red pattern, as if the green one were obliterated. The
former effect takes place when the eyeis steadily fixed on the green
part, and the latter, when it is steadily fixed on the red portion.
Provide two lighted candles, and place them upon a table be-
fore a whitewashed or light papered wall: hold before one of the
candles a piece of coloured glass, taking care to remove to a greater
distance the candle before which the coloured glass is not placed,
in order to equalize the darkness of the two shadows. If you use
a piece of green glass, one of the shadows will be green, and
the other a fine red; if you use blue glass, one of the shadows
will be blue, and the other a pale yellow.
COLOURS OF SCRATCHES.
An extremely fine scratch on a well-polished surface, may be
regarded as having a concave, cylindrical, or, at least, a curved
surface, capable of reflecting light in all directions; this is evident,
for it is visible in all directions. Hence, a single scratch or furrow
in a surface, may produce colours by the interference of the rays
reflected from its opposite edges. Examine a spider's thread in
the sunshine, and it will gleam with vivid colours. These may
arise from a similar cause, or from the thread itself, as spun by
the animal, consisting of several threads agglutinated together, and
thus presenting, not a cylindrical, but a furrowed surface.
SIGHT AND BOUND.
One of the most curious affections of the eye is that, in virtue
of which it sees what are called ocular pectra, or accidental
colours. If we place a red wafer on a sheet of white paper, and,
closing one eye, keep the other directed for some time to the
centre of the wafer, thep, if we turn the same eye to another part
of the paper, we shall see a green wafer, the colour of which will
continue to grow fainter and fainter, as we continue to look at it
By using differently coloured wafers, we obtain the following
Black . White.
White . Black.
Red . Bluish Green.
Orange. . Blue.
Yellow . Indigo.
Green . Violet, with a little Red.
Blue. . Orange Red.
Indigo . Orange Yellow.
Violet . Bluish Green.
BEAUTIFUL COLOURS OF MOTHEI-OF-PEAKL.
This substance, obtained from the shell of the pearl oyster, is
much admired for the fine play of its colours. To observe them
accurately, select a plate of regularly formed mother-of-pearl, with
its surface nearly parallel, and grind this surface upon a hone,
or upon a plate of glass, with the powder of slate, till the image of
the candle, reflected from the surfaces, is of a dull reddish white
colour, when it will glow with all the colours of the rainbow. The
8lOrT AND sOUND.
odours of mother-of-pearl may communicated to soe black
wax; and to clean surfaces of lead and tin by hard preure, or the
blow of a hammer. Or, dinolve gum ara or isinglaM, in water,
and allow it to harden upon a surface of mother-of-pearl, when
it will take a perfect impression from it, and exhibit all the colours
in the nest manner. Or, place the isinglas between to inely-
polished surfaces of mother-of-pearl, and you may obtain a iha of
artificial mother-of-pearl, which, when seen by the light of a can-
dle, or by an aperture in the window, will shine with the brightest
WHITE LETTERS SEEN FURTHER THAN BLACK.
Paint the same letters of the same size precisely on two boards,
the one white on a black ground, and the other a black on a
white ground; the white letters will appear larger, and be read at
a greater distance than the black.
Observe the various colours which are reflected from the glass
drops usually suspended from a lustre or chandelier, and you will
witness a mimic rainbow. A rainbow may also be made by a
garden engine, if the water be thrown high in the air, and the
spectator stand between it and the sun.
FRINGE ABOUT A CANDLES.
Provide two small pieces of plate glass, moisten two of their
sides with water, and put them together; then look through them
at a candle, and you will perceive the flame surrounded with
beautifully coloured fringe: these are the effect of moiture,
intermixed with portions of air, and exhibiting an appearance
similar to dew.
SIGHT AND SOUND.
THE DOUBLE COLOURED REFLECTION.
Provide a circular piece of coloured glass, and pierce its centre
by means of a common awl, well moistened with oil of turpentine:
encircle the glass with the fingers and thumb, hold it in the sun-
shine or the strong light of a lamp, and the following beautiful
elbcts will be produced. If the glass be red, the luminous spot in
the centre will be reflected green; if the glass be green, the spot
will be red; if blue, orange; and if yellow, indigo.
Place a lighted candle before a looking-glass, and there will
appear a luminous cross radiating from the flame of the candle.
Thi is produced by the direction of the friction by which the glass
is polished; the scratches placed in a horizontal direction, exhi-
biting the perpendicular part of the cross, and the vertical scratches
the horizontal part.
RIN0G OF COLOURS ROUND A CANDLE.
Look at a candle through a plate of glass, upon which you have
gently breathed, or over which are scattered particles of dust, or
any fine powder, and you will perceive the flame surrounded with
beautiful rings of colours. By using the seed of the lycopodium,
or by placing a drop of blood diluted with water between two
pieces of glass, the rings of colour will be still more finely exhi-
bited. Round the luminous body there will be seen a light area,
terminating in a reddish dark margin; this will be succeeded by a
ring of bluish-green, and then by a red ring; these two last colours
smcceeding each other several times when the particles are of uni-
form diameter, as are the seeds of the lycopodium, each of which
is but the 860th part of an inch in diameter.
SIGHT AND SOUND.
SIMPLu AND CHEAP OP1RA-GLAUS.
In this new instrument, no tubes are necessary, a in the
ordinary opera-glass; their place being supplied by a slender
a elastic conical spring of wire, into the upper extre-
mity of which is inserted the eye-glass; the object-
glass being fixed to the other extremity, as shewn
in the engraving. The two glases must, ofcourse,
be kept parallel to each other when in use; which
is very easily effected.
In using this opera-glass, rest the finger and
thumb of one hand on the rim of the object-glass,
B, whilst, with the thumb and finger of the other
hand you hold the rim of the eye-glas, A. The
spring tube may then be drawn out or shut up to
very minute distances. Thus, the ordinary sliding tubes are super-
seded nor is any external covering necessary, as the hand in grap-
ing the instrument serves the purpose. It however, a covering be
preferred, a piece of silk may be sewn to the spirals of the spring.
This kind of opera-glass may be made very cheaply: it may
be shut into a small space for the pocket, merely by pressing the
object-glass and eye-glass together.
Place two pieces of looking-glass, one at each end, parallel to
one another, and looking over, or by the edge of one of them, the
images of any objects placed on the bottom of the box, will appear
continued to a considerable distance.
Or, line each of the four sides of the box with looking-glas, and
the bottom of the box will be multiplied to an astonishing extent,
SIGHT AND SOUND.
there being no other limitation to the number of images but what
is owing to the continued loss of light from reflection. The top
of the box may be almost covered with thin canvas, which will
admit sufficient light to render the exhibition very distinct.
The above experiments may be made very entertaining, by
placing on the bottom of the box some toy, as two persons playing
at cards, sentry soldiers, &c.; and, if these be put in motion, by
wires attached to them, or passing through the bottom or side of
the box, it will afford a still more entertaining spectacle. Or the
bottom of the box may be covered with moss, shining pebbles,
flowers, &c.; only, in all cases, the upright figures between the
pieces of looking-glass should be slender, and not too numerous,
else they will obstruct the reflected light.
In a box with six, eight, or more sides, lined with looking-
glass, as above, the different objects in it will be multiplied to an
almost indefinite extent.
APPARATUS FOR WRITING IN THE DARK.
In this ingenious contrivance, A is a frame of wood, into the
back and front of which are inserted two thin boards, the front
one, B, reaching about half the height of
the frame, and the back one being movea-
Sble, by sliding in grooves, for better fixing
the paper to be written on, C, to a roller at
top, with a handle and ratchet working into
To use the apparatus, the paper is to be
S fixed on the roller, and a strip of lead or
other weight, suspended from the bottom of the paper, to keep it
SIGHT AND SOUND.
smooth: then, by resting the right hand on the edge of the board,
B, and turning, with the left hand, the ratchet, the distance of the
lines may be regulated by the number of clicks caused by the
spring on the ratchet. D, is a foot to support the apparatus;
which, however, should be light enough to be held in the hand as
This cheap and useful instrument consists of a handle of hard
wood, a, which is screwed into a brass piece, d, having, at its top,
a ring, which screws on back and front, into
which are to be screwed two cells with lenses
S of different foci. There is also a projecting
piece formed on the side of the brass piece,
Sd, in which is a hole to receive the screwed
end of a cylindrical rod of brass, c. Upon
this rod, a springing slit socket, e, slides
S 'a backwards and forwards, and is also capable
of being turned round. This socket has
affixed to it, on one side, a projecting part,
with a screwed cavity in it, to receive a short screwed tube, with a
small hole in its centre, made to fit the steel stem of the spring
forceps; a corresponding hole being made at the bottom of the
screwed cavity, where is lodged a piece of perforated cork; which,
being pressed upon by the action of the screw, closes upon the steel
stem of the forceps, and steadies them, and the objects held in
them. The stem of the forceps being removed from its place in the
short tube; the handles and lenses, and the rod, c, and the sliding
socket upon it, being unscrewed from its place in the handle;
they can all three be packed in a black paper case, which is only
three and a half inches long, one inch broad, and .half an inch
SIGHT AND SOUND.
This microscope possess three different magnifying powers,
namely, those of two lenses separately, and the two in combination.
Microscopes of a still simpler nature are small globules o glass,
formed by smelting the ends of fine threads of glass in the flame of
a candle; and small globular microscopes of great magnifying
power, made of hollow glass about the size of a small walnut, may
be purchased very cheaply at the opticians'.
THE PHENAKISTICOPE, OR STOBOSCOPE.
This amusing instrument consists of a turning wheel, upon
which figures are seen to walk, jump, pump water, &c. The disk
or wheel should be of stout card-board, upon which should be
painted, towards the edge, figures in eight or ten postures. Thus,
if it is wished to represent a man bowing, the first position is a man
standing upright; in the second, his body has a slight inclination;
in the third, still more; and so on, to the sixth position, where the
body is most bent: the four following, represent the figure reco-
vering its erect posture, so that the fifth and seventh, the fourth
and eighth, the third and ninth, the second and tenth figures, have
the same posture. Between each of the figures on the wheel,
should be a slit, three-fourths of an inch long, and one-fourth ofan
inch wide, in a direction parallel with the radii of the wheel, and
extending to an equal distance from the centre.
To work this instrument, place the figured side of the wheel
before a looking-glass, and cause it to revolve upon its centre; then
look through the slits or apertures, and you may observe, in the
glass, the figures bowing continually, and with a rapidity pro-
portionate to the rate at which the wheel turns. The iulnue
depends on the circumstance, that the wheel between each apertre
SIGHT AND BOUND. 98
is covered, while the figure goes further. That the deception may
be complete, it is necessary that every part of the figures not
bowing shall be at an equal distance from the centre of the wheel,
and from the slits; also that the figures possess equal thickness and
TO LOOK AT THE SUN WITHOUT INJURY.
Provide a wine-glan filled with plain water, which will keep oft
the heat so effectually, that the brightest sun may be viewed some
time through it without any inconvenience. If a little black ink
be added to the water, the image of the sun will appear through it,
as white as snow; and when the ink is still more diluted, the sun
will be of a purple hue.
BRILLIANT WATER MIRROR.
Nearly fill a glass tumbler with water, and hold it, with your
back to the window, above the level of the
A eye, as in the engraving. Then look obliquely,
as in the direction E, a, c, and you will
see the whole surface shining like burnished
silver, with a strong metallic reflection;
and any object, as a spoon, A C B, im-
mersed in the water, will have its immersed
part, CB, reflected on the surface, as in a
*^ mirror, but with a brilliancy far surpassing
U that which can be obtained from quicksilver,
or from the most highly-polished metals.
OPTICAL ILLUSION UNDER WATER.
Procure a large gallipot; place on the bottom, next the side
furthest from you, a sixpence, and next to it, but towards the centre,
8iHT AND SOUND.
a shilling; move to such a distance as will render the coins in-
visible; then let another person pour water gently in, and as
it rises in the gallipot, it will cause both the sixpence and shil-
ling to be seen, without your approaching nearer to the gallipot,
or moving it towards you.
THE MAGIC WHEELS.
Cut out two card-board cog-wheels of equal size; place them
upon a pin, and whirl them round with equal velocity in opposite
directions; when, instead of producing a hazy tint, as one wheel
would do, or as the two would if revolving in the same direction,
there will be an extraordinary appearance of a fixed wheel. If
the cogs be cut slantwise on both wheels, the spectral wheel, as it
may be called, will exhibit slanting cogs; but if one of the wheels
be turned, so that the cogs shall point in opposite directions, then
the spectral wheel will have straight cogs. If wheels with radii,
or arms, be viewed when moving, the deception will be similar;
and however fast the wheels may move, provided it be with equal
velocity, the magic of a fixed wheel will be presented.
Or, cut a card-board wheel with a certain number of teeth or
cogs at its edge; a little nearer the centre, cut a series of apertures
resembling the cogs in arrangement, but not to the same number;
and still nearer the centre cut another series of apertures, different
in number, 'and varying from the former. Fix this wheel upon
another, with its face held two or three yards from an illuminated
mirror; spin it round, the cogs will disappear, and a greyish belt,
three inches broad, will become visible; but, on looking at the glass
through the moving wheel, appearances will entirely change: one
row of cogs, or apertures, will appear fixed, as if the wheel were
not moving, whilst the other two will appear as if in motion; and,
by shifting the eye, other and new effects appear.
SIGHT AND SOUND.
These amusing deceptions were first experimented by Mr.
Faraday. The simple apparatus for their exhibition may be
purchased, for a trifling sum, of any respectable optician.
A sounding-plate, made of brass, nine inches long, and half a
line in thickness, covered with a layer of water, may be employed
to produce a rainbow in a chamber which admits the sun. On
drawing a violin bow strongly across the plate, so as to produce
the greatest possible intensity of tone, numerous drops of water fly
perpendicularly and laterally upwards. The size of the drops is
smaller as the tone is higher. The inner and outer rainbows are
very beautifully seen in these ascending and descending drops, when
the artificial shower is held opposite to the sun. When the eyes
are close to the falling drops, each eye sees its appropriate rainbow;
and four rainbows are perceived at the same time, particularly if
the floor of the room is of a dark colour. The experiment succeeds
best, if, when a finger is placed under the middle of the plate, and
both of the angular points at one side are supported, the tone is
produced at a point of the opposite side, a fourth of its length from
one of its angles. An abundant shower of drops is thus obtained.
TRANSMISSION OF SOUND.
Suspend any sonorous body, as a bell, a glass, a silver spoon,
or a tuning-fork, from a double thread, and put with the finger the
extremities of the thread, one in each ear; if the body be then
struck, the apparent loudness and depth of the sound will be sur-
Again, if you shut your ears altogether, you will yet feel very
SIGHT AND SOUND.
sensible of the impression of any sound conveyed through the
mouth, the teeth, or the head: if you put one end of a small stick
or rod in the mouth, and touch with the other extremity a watch
lying on the table, the beatings will become quite audible, though
the ears be actually shut. So, also, if a log of wood be scratched
at one end with a pin, a person who applies his ear to the other
end will hear the sound distinctly.
Fogs and falling rain, but especially snow, powerfully obstruct
the free propagation of sound; and the same effect is produced by
a coating of fresh-fallen snow on the ground, though when glazed
and hardened at the surface by freezing, it has no such influence.
Over water, or a surface of ice, sound is propagated with re-
markable clearness and strength. Dr. Hutton relates, that on a
quiet part of the Thames, near Chelsea, he could hear a person
distinctly at 140 feet distance, while on the land the same could
only be heard at 76 feet. Lieutenant Forster, in the third Polar
expedition of Captain Perry, held a conversation with a man
across the harbour of Port Bowen, a distance of 6696 feet, or
about a mile and a quarter. This, however remarkable, falls
short of what is related by Dr. Young, on the authority of the
Rev. W. Derham, ms. that, at Gibraltar, the voice has been heard
ten miles, perhaps, across the strait.
The cannonade of a sea-fight between the English and Dutch,
in 1672, was heard across England as far as Shrewsbury, and even
in Wales, a distance of upwards of 200 miles from the scene of
At Caribrook Castle, in the Isle of Wight, is well 210 feet
in depth, and twelve feet in diameter, into which if a pin be
dropped, it will be distinctly heard to strike the water. The
interior is lined with very smooth masonry.
SIGHT AND SOUND.
POoQI1Ss 01 sOUND.
A stretched string, u that of a piano-forte, may be nade to
vibrate not only from end to end, but in aliquot parts, the portions
being separated by points of rest which interrupt the progress of
the found. This kind of effect may be shewn by shaking a long
piece of cane in the air, when there will be one, two, or three
points of rest, according to the mode of vibrating it.
An elastic surface has, likewise, some parts in motion and
others at rest; and these parts may be made visibly distinct, by
strewing pieces of bristle over them upon the sounding-board of an
When a bow is drawn across the strings of a violin, the im-
pulses produced may be rendered evident by fixing a small steel
bead upon the bow; when looked at by light or in sunshine, the
bead will seem to form a series of dots during the passage of
BOUND TURNING CORNERS.
Take a common tuningfork, strike it, and hold it (when set in
vibration) about three or four inches from the ear, with the flat
side towards it, when the sound will be distinctly heard; let a strip
of card, somewhat longer than the flat of the tuning-fork, be inter-
posed at about half an inch from the fork, and the sound will be
almost entirely intercepted by it; and, if the card be alternately
removed and replaced in pretty quick succession, alternations of
sound and silence will be produced; proving that sound is by no
means propagated with so much intensity round the edge of the card,
as straight forward. Indeed, to be convinced of this fact, you have
only to listen to the sound of a carriage turning a corner from the
street, in which you happen to be, into an adjoining one. Even
38 8IGHT AND SOUND.
where there is no obstacle in the way, sounds are by no mesa
equally audible in all directions from the sounding body; as you
may ascertain, by holding a vibrating tuning-fork or pitch-pipe
near your ear, and turning it quickly on its axis.
TO TILL THE DISTANCE 01 THUNDER.
Count, by means ofa watch, the number of seconds that elapse
between seeing the flah of lightning and hearing the report of the
thunder: allow somewhat more than five seconds for a mile, and
the distance may be ascertained. Thus, say the number ofseconds is
4 miles distant;
or the distance may be estimated by remarking the number of
beats of the pulse in the above interval; provided, of course, that
we know the rate at which the pulse beits in a certain time. In a
French work, it is stated that if the pulse beat six times, the
distance of the thunder will be about 30,000 feet, or fives miles and
a half; thus reckoning 5,000 feet for each pulsation.
In a violent thunder-storm, when the sound instantly succeeds
the flash, the persons who witness the circumstance are in some
danger; when the interval is a quarter ofa minute, they are secure.
BEARING BT THE TOUCH.
If a deaf person merely place the tips of his finger-nails on
the windoW-shutters or door of a room in which instruments are
playing, he may enjoy their concert of harmony.
CONVlERATION 1OR THE DEAF.
If two persons stop their ears closely, they may converse with
each other by holding a long stick or sticks between their teeth, or
SIGHT AND SOUND.
by nesting their teeth against them. The person who speaks may
rest the stick against his throat or his breast; or he may rest the
stick which he holds in his teeth, against a glass tumbler or china
basik into which the other speaks. The sound may also be heard
when thread is held between the teeth by both persons, so as to
be somewhat stretched.
GLASS BROKEN BY TUE VOICE.
01 vibrating bodies, which present a large surface, the effects
of samds are very surprising. Persons with a clear and powerful
voice have been known to break a drinking-glass, by singing the
proper fundamental note of their voice close to it. Looking-glasses
are dso said to have been broken by music, the vibrations of the
atoms of the glass being so great as to strain them beyond the
limits of their cohesion.
VIGULRS PRODUCED BT BOUND.
Stretch a sheet of wet paper over the mouth of a glass tumbler
which has a footstalk, and glue or paste the paper at the edges.
When the paper is dry, strew dry sand thinly upon its surface.
Place the tumbler on a table, and hold immediately above it, and
parallel to the paper, a 'plate of glass, which you also strew with
sand, having previously rubbed the edges smooth with emery pow-
der. Draw a violin bow along any part of the edges, and as ths
sand upon the glass is made to vibrate, it will form various figures
which will be accurately imitated by the sand upon the paper; or,
if a violin or flute be played within a few inches of the paper,
they will cause the sand upon its surface to form regular lines and
40 SIGHT AND SOUND.
Provide a long, flat glass ruler or rod, as in the engraving, ad.
cement it with mastic to the edge of a drinking-glass fixed ino a
wooden stand; support the other end of the rod very lightly on a
-m= piece of cork, and strr its
upper surface with and;
_et the glass in vibratis by
a bow, at a point opposite
where the rod meets it, and the motions will be communicated to
the rod without any change in their direction. If the appartu
be inverted, and sand be strewed on the under side of the rod, the
figures will be seen to correspond with those produced on the
Provide two disks of metal or glass, precisely of the same
dimensions, and a glass or metal rod; cement the two disks at
their centres to the two ends of the rod, as
Sin the engraving, and strew their upper
surfaces with sand. Case one of the dis,
els. the upper one, to vibrate by a bow, and
its vibration will be exactly imitated by the
lower disk, and the sand strewed over both
will arrange itself in precisely the same
forms on both disks. But if, separately,
they do not agree in their tones, the figures on them will not
CHAMPAOGN AND SOUND.
Pour sparkling champagne into a glass until it is half f1,
when the glass will lose its power of ringing by a stroke upon its
SIGHT AND SOUND.
edges and will emit only a disagreable and pur mound. Nor
will the glass ring while the wine s brick, and filled with air
bubbles; but, as the elervescence subsides the sound will become
clearer and clearer, and when the air bubbles have entirely dis-
appeared, the glass will ring as usual. If a crumb of bread be
thrown into the champagne, and effervescence be reproduced, the
glass will again cease to ring. The same experiment will al"o
succeed with soda-water, ginger wine, or any other efferveeing
MUSIC FROM PALISADES.
If a line of broad palisades, set edgewise in a line directed from
the ear, and at even distance* from each other, be struck at the
end nearest the auditor, they will reflect the sound of the blow,
and produce a succession of echoes: these, from the equal distance
of the palisades, will reach the ear at equal intervals of time, and
will, therefore, produce the effect of a number of impulses originat-
ig in one point. Thus, a musical note will be heard.
THEORY F0 THE JEW'S HARP.
If you cause the tongue of this little instrument to vibrate, it
will produce a very low sound; but if you place it before a cavity
(as the mouth), containing a column of air, which vibrates much
faster, but in the proportion of any simple multiple, it will then
produce other higher pounds, dependent upon the reciprocation
of that portion of the air. Now, the bulk of air in the mouth
can be altered in its form, sise, and other circumstances, so as to
produce, by reciprocation, many different sounds; and these ae
the sounds belonging to the Jew's Harp.
SIGHT AND SOUND.
A proof of this fact has been given by Mr. Eulenstein, who
fitted into a long metallic tube a piton, which, being moved, could
be made to lengthen or shorten the efficient column of air within
at pleasure. A Jew's Harp was then so fixed that it could be
made to vibrate before the mouth of the tube, and it was found that
the column of air produced a series of sounds, according as it was
lengthened or shortened; a sound being produced whenever the
length of the column was such that its vibrations were a multiple
of those of the Jew's Harp.
MUSIC OW THE SNAIL.
Place a garden-snail upon a pane of glass, and, in drawing
itself along, it will frequently produce sounds similar to those of
TO TUNE A GUITAR WITHOUT THE ASSISTANCE OF THE EAR.
Make one string to iound, and its vibration will, with much
force, be transferred to the next string: this transference may be
seen, by placing a saddle of paper (like an inverted a) upon the
string, at first in a state of rest. When this string Aears the
other, the saddle will be shaken, or fall off; when both strings
are in harmony, the paper will be very little, or not at all, shaken.
MUSIC PROM OLA88 OR METAL ROD8.
Provide a straight rod of glass or metal; strike it at the end in
the direction of its length, or rub it lengthwise with a moistened
fnger, and it will yield a musical sound, which, unless its length be
very great, will be of an extremely acute pitch; much more so
than in the case of a column of air of the same length, as in a
SIGHT AND SOUND.
flute. The reason of this is the greater velocity with which sound
is propagated in solids than in the air. If the rod be metal, the
friction will be found to succeed best when made with a bit of
cloth, sprinkled with powdered rosin; or, if of glass, the cloth
or the finger may be moistened and touched with some very fine
sand or pumice powder.
Generally speaking, a fiddle-bow, well resigned, is the readiest
and most convenient means of setting solid bodies in vibration.
To bring out their gravest or fundamental tones, the bow must be
pressed hard and drawn slowly; but, for the higher harmonies,
a short, swift, stroke, with light pressure, is most proper.
THE TUNING-FORK A FLUTE PLAYER.
Take a common tuning-fork, and on one of its branches fasten
with sealing-wax a circular piece of card, of the size of a small
_ wafer, or sufficient nearly
to cover the aperture of a
pipe, as the sliding of the
upper end of a flute with the mouth stopped: it may
be tuned in unison with the loaded tuning-fork (a
C fork), by means of the moveable stopper or card,
or the fork may be loaded till the unison is perfect
Then set the fork in vibration by a blow on the unloaded
branch, and hold the card closely over the mouth of the pipe,
as in the engraving, when a note of surprising clearness and
strength will be heard. Indeed, a flute may be made to "speak"
perfectly well, by holding close to the opening a vibrating tuning-
fork, while the fingering proper to the note of the fork is at the
same time performed.
44 SIGHT AND SOUND.
Provide two glass bottles, and tune them by pouring water into
them, so that each corresponds to the sound of a different tuning-
fork. Then apply both tuning-forks to the mouth of each bottle
alternately, when that sound only will be heard, in each cae,
which is reciprocated by the unisonant bottle, or, in other words,
by that bottle which contains a column of air, susceptible of
vibrating in unison with the fork.
THEORY OF WHISPERING.
Apartment* of a circular or elliptical form are best calculated
for the exhibition of this phenomenon. If a person stand near the
wall, with his face turned to it, and whisper a few words, they may
be more distinctly heard at nearly the opposite side of the apart-
ment, than if the listener was situated nearer to the speaker.
THEORY 01 T H VOICE.
Provide a species of whistle, common as a child's toy or a
sportman's call, in the form of a hollow cylinder, about three-
fourths of an inch in diameter, closed at both ends by flat circular
plates, with holes in their centres. Hold this toy between the
teeth and lips; blow through it, and you may produce sounds
varying in pitch with the force with which you blow. If the air
be cautiously graduated, all the sounds within the compass of a
double octave may be produced from it; and, if great precaution
be taken in the management of the wind, tones even yet graver
may be brought out. Thi simple instrument, or toy, has, indeed,
the greatest resemblance to the larynx, which is the organ of voice.
A speaking-machine has been invented in Germany, with which
BIGHT AND SOUND.
have been distinctly pronounced the words, mamma, papa, moUter,
father, smmer. This instrument consists of a pair of bellows, to
which is adapted a tube terminating in a bell, the aperture of
which is regulated by the hand, so as to produce the articulate
SOUND ALONG A WALL.
Whisper along the bare wall of an apartment, and you will be
heard much further than in the middle of the room; for the trough
or angle between the wall and the floor, forms two sides of a square
pipe which conveys the sound.
SOUNDS MORE AUDIBLE BY NIGHT THAN BY DAT.
The experiment with the glass of champagne (page 40) has
been employed by Humboldt, in explanation of the greater
audibility of distant sounds by night than by day. This he attri-
butes to the uniformity of temperature in the atmosphere by night,
when currents of air no longer rise and disturb its equilibrium;
as the air-bubbles in the champagne interfere with the vibration
within the glass. Again, the universal and dead silence gebe-
rally prevalent at night, renders our auditory nerves sensible to
sounds which would otherwise escape them, and which are in-
audible among the continual hum of noises which is always going
on in the day time.
If a noise be made in a narrow passage, or apartment of
regular form, the echoes will be repeated at equal very small
intervals, and will always impress the ear with a musical note.
This is, doubtless, one of the means which blind persons have of
judging of the size and shape of any room they happen to be in.
SIGHT AND SOUND.
The main secret of this surprising art simply consists in firt
making a strong and deep inspiration, by which a considerable
quantity of air is introduced into the lungs, to be afterwards acted
upon by the flexible powers of the larynx, or cavity situated behind
the tongue, and the trachea, or windpipe: thus prepared, the
expiration should be slow and gradual. Any person, by practice,
can, therefore, obtain more or less expertness in this exercise; in
which, though not apparently, the voice is still modified by the
mouth and tongue; and it is the concealment of this aid, that
much of the perfection of ventriloquism lies.
But the distinctive character of ventriloquism consists in its
imitations being performed by the voice seeming to come from the
stomach: hence its name, from veater, the stomach, and loguor,
to speak. Although the voice does not actually come from that
region, in order to enable the ventriloquist to utter sounds from
the larynx without moving the muscle* of his face, he strengthens
them by a powerful action of the abdominal muscles. Hence, he
speaks by means of his stomach; although the throat is the real
source from whence the sound proceeds. It should, however, be
added, that this speaking distinctly, without any movement of the
lips at all, is the highest perfectionof ventriloquism, and has but
rarely been attained. Thus, MM. St. Gille and Louis Brabant, two
celebrated French ventriloquists, appeared to be absolutely mute
while exercising their art, and no change in their countenances
could be discovered.
It has lately been shewn, that some ventriloquists have acquired
by practice the power of exercising the veil of the palate in such a
manner, that, by raising or depressing it, they dilate or contract
the inner nostril. If they are closely contracted, the sound pro-
SIGHT AND SOUND.
doced i week, dull, and eems to be more or le distant; if on
the contrary, these cavities are widely dilated, the sound will be
strengthened, the voice become loud, and apparently close to us.
Another of the secrets of ventriloquism, is the uncertainty with
respect to the direction of sounds. Thus, if we place a man and a
child in the same angle of uncertainty, and the man speaks with
the accent of a child, without any corresponding motion in his
mouth or face, we shall necessarily believe that the voice comes
from the child. In this case, the belief is so strengthened by the
imagination; for if we were directed to a statue, as the source from
which we were to expect sounds to issue, we should still be
deceived, and refer the sounds to the lifeless stone or marble.
This illusion will be greatly assisted by the voice being totally
different in tone and character from that of the man from whom
it really comes. Thus, we see how easy is the deception when the
sounds are required to proceed from any given object, and are
such as they actually yield.
The ventriloquists of our time, as M. Alexander and M.
Fits-James, have carried their art still further. They have not
only spoken by the muscles of the throat and the abdomen,
without moving those of the face, but have so far overcome the
uncertainty of sound, as to become acquainted with modifications
of distance, obstruction, and other causes, so as to imitate them
with the greatest accuracy. Thus, each of these artists has sue-
ceeded in carrying on a dialogue; and each, in his own single
person and with his own single voice, has represented a scene
apparently with several actors. These ventriloquists have likewise
possessed such power over their faces and figures, that, aided
by rapid changes of dress, their personal identity has scarcely
been recognized among the range of personations.
48 SIGHT AND SOUND.
Vocal imitations an much les striking and ingenious than the
feet of ventriloquism. Extraordinary varieties of voice may be
produced, by speaking with a more acute or grave pitch than
usual, and by different contractions of the mouth. Thus may be
imitated the grinding of cutlery on a wheel, the sawing of wood,
the frying of a pancake, the uncorking of a bottle, and the
gurgling noise in emptying its contents.
LIGHT & HEAT.
FLASHES 0O LIGHT UPON REVOLVING WHEELS,
SRnovIDEn a circle of card-board, six inches in dia-
meter; divide itinto sixteen parts, and paint them
alternately red and black. Provide a second
circle or disk of the same size, and paint on it,
in large characters, the words At rest," on a
white ground. Connect both disks with the smn-
ple apparatus for causing them to turn round,
used in the construction of a toy windmill. Next fill a basin with
water, and provide a few small pieces of phosphuret of lime:
darken the room, hold the disks over the basin, and turn them
round; let the phosphuret of lime be put into the water, and bubbles
of light will rise to its surface. If they come up slowly, both disks
will appear stationary during their turning round; but when the
bubbles come up quickly, the black and red spaces will exhibit a
dancing motion, and sometimes two black spaces will msem joined
L3@N7 ANi~D MIA'i.
LIGHT AND HRAT.
into one, to the exclusion of the intervening red, and ek. wrrd:
the words on the econd disk will alo croa each other in various
direetonu, when the lahee of light interfere; and, in both aoes,
consaion will be excited by a impression being made on the
reins before preceding impresions have departed.
DMCOMFOIITION 01 LIGHT.
Sir Isma Newton irst divided a white ray of light, and found
it to consist of an smemblage of coloured rays, which formed an
image upon a wall, and in which were displayed the following
colourn: red, orange, yellow, green, blue, indigo, and violet. Sir
saac then chewed that thee seven colours, when again put toge-
ther or combined, recomposed white light. This may be proved
by painting a card wheel in circles with the above colours, and
whirling it rapidly upon a pin, when it will appear white.
Lght may also be decomposed by the following beautiful
eaperimet:-Form a tube, about tea inches long and one inch in
damoe, of paper, one ide of which is of a bright blue colour.
Ths may be dane by wrapping the paper once round a cylhUme do
wod, sa securing the edges f the paper with paote. The coloured
ide of the paper must be the interior of the tube. Apply this
tkbe to on eye, the other being closed, and on looking at the
sailing, a circular orange spot will be men, which is the remlt of
deeompaition: the white light from the ceiling enters the tube,
the blue i retained, and the red and yellow rays enter the eye,
and produce the impression of orange.
T'l they of solar refetion may be beautiftuly illastrtd a
fellow: Put a killing into a basin, and pour me water n it, .
whie the lver will be rebted through the medium; ad, if the
LIOT AND BUAT.
vsdl be killed, you may withdraw to may distance Aem wbih the
surface of the water will be visible, and, by the re ration rom it
you can till obeerre the hflling.
Dissole crytals of nitrate of copper in spirit of wine; light
the solution, and it will burn with a beautiful emerald-green fme:
pieces of sponge soaked in this spirit, lighted and senpended by
fine wires over the stage of theatre, produce the lambent green
fames now so common in incantation scene: strips of flannel
sturated with it, and applied round copper sword, tridents, &c.
produce, when lighted, the faming swords and fire-fork bran-
dished by the demons in such scene: indeed, the chiefconsumption
of nitrate of copper is for these purposes.
TO IMITATE TE LIGHT F0 TH IsA.
It is well known, that on dark, stormy nights, the see emits a
brilliant light, the effect of which may thus be imitated. Scrape
of four drams of the substance of putrefying fh, as whiting her-
ring or mackerel, and put it into a white glass bottle, containing
two ounces of sea-water, or of pure water with two drams of
common alt dissolved in it; set the bottle in a dark place, and in
three day a ring of light will be seen on the suare of the liquid,
and the whole, if shaken, will become luminous, and continue so for
some time. If it be et in a warm place, the light will be brighter;
if the liquid be fosen, the light will disappear, but will re-appear
on being thawed.
If more salt be added to the solution, the lght will disappear,
but instantly burst frth from absolute darkness by dilation with
water. Lime water, common water, beer, adds, even very dilute
LIGHT AND HBAT.
alkaline leys, as pearl-ah or soda and water, will permanently
extinguish this spontaneous light.
The oxygenated, or ekorate mates, are first dipped in melted
sulphur, and then tipped with a paste made of chlorate of potass,
sulphur, and sgar, mixed with gum-water, and coloured with
vermilion: frankincense and camphor are sometimes mixed with
the compodtion, and the wood of the match is pencil-cedar, so that
a fragrant odour is diflsed by the matches in burning. To obtain
light, a match is very lightly dipped in a bottle containing a little
asbestos soaked in oil of vitriol.
Lufser consipt of chips of wood tipped with a paste of chlorate
of potme mixed with sulphuret of antimony, starch, and gum-
water: when a match is pinched between the folds of glas-paper,
and suddenly drawn out, a light is instantly obtained.
PromuteAe consist of small rolls of waxed paper, in one end
of which is a minute quantity of vitriol, in a glass bulb, sealed up,
and surrounded with chlorate of potass: when the end thus pre-
pared is presed so as to break the bulb, the vitriol comes in
contact with the composition, and produces light instantly.
For cigar-smokers, Prometheans are made with touch-paper;
this ignites from the composition, and glows without fame, like a
slow match; and as'the wind will not extinguish it, a dry cigar
may be readily lighted at it.
Lucifers and Prometheans must be used with caution, and
should never be carelesly left about: by letting them fall upon a
sanded floor, and being accidentally trod upon, they may take nre,
and thus do great mischief.
LI@*9 AND HIM'.
TO COLOUR TIn rLASB 01 A CAUDL.
Take a piece of pkthread, or cotton third, boil it in eled
Water to fee it from line particle, and dry it; wet one end, and
take up on it a little of either of the salts hereafter named, in fin
powder, or strong solution. Then dip the wetted end ofthe thread
into the cup of a burning wax candle, and apply it to the exterior
of the flame, not quite touching the luminous part, but 16 a
to be immersed in the cone of invisible but intensely heated air
which envelopes it. Immediately, an irregular sputtering com-
kustion of the wax on the thread will take place, and the invisble
tone of heat will be rendered luminous, with a peculiarly coloured
light, according to the ialt employed.
Thus, common salt will give a bright yellow; muriate of
potas will give a beautiful pale violet; muriate of lime will give a
brik red; muriate of ttrotia will give a magnificent crimson;
mriste of lithia will give a red; muriate of beryta will give a fine
pale apple green; muriate of copper will give a beautiful bluish
green; and green copper will give a white light.
TO DIVIDE THE FLAME OF A CANDLE.
Provide about a foot square of bras or iron wire gauze, of the
finenes of thirty meshes to the square inch: lower the gaue upon
the nsse of a wax candle, which will not rie through the mehes,
but in its place will be the inflammable smoke of the flame; apply
to this a piece of lighted paper, and it will be kindled, and the
candle will burn with fme above and beneath the game. In
this case, the gauze so cools the flame, a to exinguish it; aad
upon this principle is constructed the Davy Seety Lamp, in whieh
the light is mrrunded with wireause
LIORT AND HBAT.
To vry this experiment, place a chip of camphor in the centre
oa piece of wire-gane about a foot qure, and hold it over the
ame of a candle or lmp; when the vapour of the camphor will
burn brightly upon the lower uaace of the gase, but cannot rise
through it, in coequence of its cooling power. Thus, the
camphor ies upon the gau in an uninflamed state, though it is
sdioiently heated to yield inflammable vapour to feed a fame
CAMN WICX LAMP.
Cut a piece of cane about one inch long; set it upright in
spirit of wine, with a smll portion just above the surfce: the
spirit wil then rise through the tube of the cane, which, being
lighted, will burn a a wick.
CAPRHOX AND PLATINUM LAMP.
Place a smal piece of eamphor, or a few fagments, upon the
bottom of a gls, and lay upon the camphor a pice of coiled or
pressed up platinum wire, heated in the flame of a lamp; when
the platinum wll glow brilliantly as long a any camphor reminu,
and frequently light up into lame.
PLATINUM AND ITHER LAMP.
Put into a mall hyacinth-glass a tea-spoonl of
ether, and suspend in it, by wire, a coil of fn pla
tinum wire, firt heated in the fame of a spirit lamp;
the wire will then glow with a red beat, and aome
of it may become white hot; in the latter ease, lame
will be produced by the ether burng.
LIGHT AND ELAT.
Cut a hip of camphor; light it, and t it on a besn ea ta,
when it will continue to bum and flt until it is eonsumd.
SIVU TITUT 0 TOR A WAX TAPEL
Steep a loosely twisted cotton skein in a solution of nitre; dry
it, and it will readily kindle by the sparks produced from the lint
and steel. It however, the cotton be further prepared by coating
portions of it, at regular intervals, alternately with sulphur and
white wax, and the sparks be struck upon the sulphur, it will
readily kindle, sad as readily light the wax; and the flam will
endure long enough for aling a letter.
Place a very stale fih in a dark room, and it will give out
a strong light, because of the numerous animalculs, whose growth
the putrefaction has promoted.
THE LUKINOU8 1ECTI0El
Phosphorus in it pure state should be very cautiouly han-
died; a, unless used very moderately, it will burn the sin.
By adding to it, however, ix part of olive oil, it may be employed
with perfect safety. If every part of the face, except the eye and
mouth, which rbould be kept shut while applying it, be -aohted
with this mixture, it will give the party a most frightful appearance
in the dark. The eye and mouth will oem black, and all the
other parts of the fes will appear lighted with a sickly, palebluih
SLItOHT AND HBATb
LIGHT, A PAINTER.
Strain a piece of paper or linen upon a wooden frame, and
ponge it over with a solution of nitrate of silver in water; place it
behind a painting upon glass, or a stained window-pane, and the
light, traversing the painting or figures, will produce a copy of it
upon the prepared paper or linen; those parts in which the rays
were least intercepted being the shadows of the picture.
BlfECT Of LIGHT UPON CRYSTALIZATION.
Place a solution of nitre in a small basin of water, in a room
which has the light admitted only through a small hole in the
window-hutter; crytals will then form most abundantly upon the
side of the basin exposed to the aperture through which the light
enter; and often the whole mas of crystals will turn towards it.
This peculiar effect may also be seen in the crystals in camphor
glasses in druggists' window, which are always most copious upon
the side exposed to the light.
Xt10CT 01 LIGHT ON PLANTS.
Shut a plant up in a room into which light is only admitted
through a mall hole in the window-shutter, and set the plant out
of the direction of this light; it will, in a short time, turn itself
and even grow downwards, that it may expose its leaves to the light.
If plants be kept in darkness, they will soon become bleached;
then, if they be exposed to the sun for three, four, or five hours,
the leaves and talks will become a intensely green as if thb
plants had been reared in the sun. Again, if a lighted lamp be
introduced into dark room, wherein a plant has been shut up aad
LIGHT AND HlAT,
bleached, it wl be e gsmin, md direct itslt towm the tp.
If such a plant be removed from the room, exposed for some time
to the sun, and then returned to darkness, it will no longer support
the privation of light, but will fade and perish.
INSTANTANEOUS LIGHT UPOM I1C.
Throw upon ice a small piece of potaiunm, and it will burst
into flame. In one experiment, the operator presed the pots-
sium on the ice with a penknife, when the whole length of the ice
WHITES LIGHT FROM ZINC.
As a substance for light, sine is far superior to any of the
metals. The light which it yields on burning is as bright as that
of the sun, and as white, so that the eye can scarcely endure it;
ad the effect is much increased by the great quantity of slvery
smoke which reflects the fire, and thus Wdely increases the sphere
of illumination. Zinc may be used in thin sheets, or in filings.
BRILLIANT LIGHT IROM TWO MITALS.
Wrap a small piece of platinum in a piece of tin-foil of the
same sie, and expoee them upon charcoal to the action of the
blow-pipe; when the union of the two metals will be accompanied
by a rapid whirling, and by a remarkably brilliant light. If the
globule thus melted be allowed to drop into a bsin of water, it will
remain for some time red-hot at the bottom of it.
BRILLIANT LIGHT FtOM 8TE3L.
Pour into a watch-glass a little sulphuret of carbon, and light
it; hold in the flame a brush of steel-wire, and it will burn beamt
filly. A watch-spring may alo be burnt in it.
LIGHT AND HIAT.
Place upon a piee of tinfoil a few powdered crystals of nitrte
of copper; moisten it with water; fold up the foil gently, and
wrap it in paper so as to keep out the air: lay it upon a plate, and
the tin will soon inflame.
LIGrT PrOM GILT BUoTONS.
Provide a new and highly-polished gilt button, and hold it in a
strong light, closely but obliquely, over a sheet of white paper, when
it will present radiations exactly like the spoke of a carriage-
wheel; the radiations being sixteen in number, and a little con-
tracted in the centre opposite the eye of the button, and presenting
altogether a beautify appearance.
LIOGH 1ROM A nLOWI.
Hold a lighted candle to the flower of the frnseua, and it
will dart forth little fashes of light. Thi beautiful appearance is
used by the essential and inflammable oil contained in mall
vessels at the extremities of the flower, which vessels burn at
the approach of any inflamed body, setting at liberty the essential
oil, a that contained in orange-peel is dischaged by pressure.
LIGHT ROM SUGAB.
Simply break a bit of lump sugar between the finger in the
dark, and light will be produced at the moment of facture.
Or, if powdered loaf sagar be put into' a spoon, fbed, and
kWdled in the lame of a lamp, it will exhibit a ne jet of flame.
LIGHT AND NtAT.
LIOHT FROM T1R POTATO.
Place a few potatoes in a dark cllar, and when they become in
a tate of putrefaction, they will give out a vivid light soffient to
read by. A few years since, an officer on guard at Strasbourg
thought the barracks were on fire, in consequence of the light thus
emitted from a cellar fall of putrefying potatoes.
LIGHT FROM THE OTITER.
Open an oyster, retain the liquor in the lower or deep shell, and,
if viewed through a microscope, it will be found to contain mult-
tude of small oyster, covered with shel, and swimming nimmy
about; one hundred and twenty of which in a row would extend
but one inch. Besides these young oysters, the liquor contains a
variety of animalcule, and myriads of three distinct species of
worms, which shine in the dark like glow-worms. Sometime, their
light reemes a blish star about the centre of the shell, which
will be beastifully luminous in a dark oom.
LIGHT rRO DnEBTIHIEls PAi
Pound, coarsely, some of the dark blue or the fetid variety of
Derbyshire spar; heat it in a dark room, in a platinum spoom, over
the low fame of a spirit-lamp, and the spar will shine with a
beautiful purple tint.
Pounded swinesoe, calcareous spar, and powdered quarts, will
alo give out light, if strewn upon a fre-hovel which has been
heated red-hot, and has just ceased glowing.
A variety of fuor spar, found in granite in Sberia, will shine
in the dart, when warmed, with remarkably strong phosphorescent
LIGHT AND HBAr.
liht increasing as th temperature is raised. The light augments
When the spar i plunged into water; and in boiling water, the
spar becomes so luminous that the letters of a printed book can be
een in a dark room near the glass containing it.
Another variety of flor spar, abo found in Siberia, is of a
pale violet colour, and emits a white light merely by the heat of
the hand; and when put into boiling water, it will give out a
LIGHT TROX OTSTER-SHELLS.
Put oyster-hells into a common fire; burn them for about half
a hour: then remove them into a dark room, when many of the
heDb will exhibit beautiful specimens of prismatic colours.
MINGS Of LIGHT IN CRTYTAL.
This i one of the most striking of optical exhibitions, and may
be thu simply produced. Provide a sheet of clear ice, about an
inch thick, frozen in till weather; let the light fall through the
iee upon a pne of window-glass, or a polished table, and by placing
a fragment of plan-gla near the eye as a refector, the most
eautil rings of light may be obeerved.
TO STRIKE LIGHT WITH CAME.
Strike a piece of rattan cane with a steel, and it contains so
much slex, or lint, that it will exhibit sparks of light in the dark.
CAUSI Of TRANSPABRNCY.
Moisten a piece of paper, and it will appear more tranparent
than when in its natural tate; the came owhih is a follows: 4,
LIGHT AND 81AT, 68
piece of dry. paper ha its pores obtraed with aely interwove
threads; these re broken by the liquor, which also fll the pore
- so many small tubes, and permits the light to pa through it,
whereas the dry threads had hitherto prevented its paage.
TRANSPAIrECT 01 GOLD.
All bodies an more or lew transparent. Thus, though gold is
one of the densest metals, yet, if a piece of the thinnest gold-leaf
be held up to a candle, the light will pass through it; and that it
paue through the substance of the metal, and not through cracks
or holes too small to be detected by the eye, is evident from the
colour of the transmitted light, which is green.
TINT CHANGED BT THICKNESS.
Provide a piece of plain and polished mal-blue glass, such a
sugr-basins and finger-glases are made of It should be of
unequal thickness. Look through this glass at a strong light,
that fom the crack of a window-hutter in a darkened room, and,
at the thinnet part, the colour will be purely blue. As the thick-
pae increases, a purple tinge will come on, which will become
more and more ruddy; and, if the glai be very thick, the olour
will par to a deep red.
SHADOWS MADE DAREBL BY INCREASED LIGHT.
Hold a finger between a candle and the wall, and it will cat a
hadow of a certain darkness: then place another candle in the
same line with the other from the wall, and, the shadow will
appear doubly dark, although there will be more light in the room
than before. Then separate the candles, and place them so as to
produce two dshdows of the finger, one partly overlapping the
other, and that part will be of double darkness, a compared with
64 LIGHT AND EIAT.
MIrnATl l TmNrDI AND ireTrxix.
To imitate thunder, provide a thin sheet of iron; hold it by
one corner between the finger and thumb, and allow it to hang
feely by its own weight. Then shake the hand horizontally, so
as to agitte the comer in a direction at right angles to the surface
of the sheet. Thus you may produce a great variety of sounds,
orom the deep growl of distant thunder to those loud claps which
rattle in rapid succesion immediately over our heads. The ame
effet may be produced by sheets of tinned iron, or tin-plate, and
by thin plates of mica; but the sound is shorter and more acute.
Partial ashes of lightning, aurora borealis, &c. may be bauti-
flly imitated by taking in a spoon about a dram of the seeds of
lycopodium, and throwing them against a lighted candle, all other
light being excluded from the room.
A dmilar effect may be produced, by laying some powdered
rein on a piece of paper, and flipping it with the finger against
the ame of a candle.
TBI B3U INaO LAMU .
R when the sun shines brightly, a piece of paper beld in
the fo of the ray drawn by the bning-lass, it will take e.
This experiment suceeds best with brown or any dark-oloured
paper; for, though the glass will collect an equal number of ray
upon white as upon coloured paper, the white paper reflect the
rays instead of allowing them to enter it; hence the white a not
so soo burnt a the coloured paper, which boring more light
than it reject, soon becomes heated, and takes re.
1AGIC 01 HRAT.
Melt a uall quanfty o the alphate of peta and coppr in
a spoem over a spirtamp; it will be aed at a heat jut bew
LIGHT AND HBAT.
redness, and produce liquid of a dark green colour. Remove the
spoon from the flame, wen the liquid will become a olid of a
brilliant emeld-green colour, and so remain til it. heat dina
nearly to that of boiling water, when suddenly a commotion wih
take place throughout the mass, beginninng fom the urfae, and
each atom, as if animated, will start up and separteitself from the
rest, till, in a few moments, the whole will become a heap of
nEPOULION BY HEAT.
Provide two smallpieces of glass; sprinkle a minute portion of
sulphur upon one piece, lay thin slips of wood around it, and place
upon it the other piece of glass. Move them slowly over the lame
of a lamp or candle, and the sulphur will become ublimed, ad
form grey nebulous patches, which are very curiodo miesaeopic
objects. Each cluster consists of thousands of transprent glo-
bule imitating, in minlsture, the nebula which we ee figured
in treatises on astronomy. By observing the largest particles, we
hall find them to be attended on one ide. Being very tnsps-
rent, each of them acts the part of a little lens, and form in its
focus the image of a distant light, which qn be perceived eve
in the smaller globules, until it vanishes ham minutenes. If they
are examined again after a certain number of hou the miller
globules willgenerally be found to have retained their transpareany,
while the larger one will have bec e opaque, in cosequence
of the sulphur having undergone some internal spontaneous change.
But the moet remarkable circumstance attending this experi-
ment is, that the globule ae found adhering to the upper glass
only; the reason of which is, that the upper glass is mewhat
cooler than the lower one; by which mean we that th vapo ,
of ulphur is very powerfully repelled by heated gla. the
LIGHT AND HNAT.
fattened form of the particle is owing to the force with which
they endeavour to recede from the lower glass, and their consequent
pressure against the surface of the upper one. This experiment is
considered by its originator, Mr. H. F. Talbot, F.R.S., to be a
matisdtory argument in favour of the repulsive power of eat.
HBAT PASSING THROUGH GLASS.
The following experiment is also by Mr. Talbot:-Heat a
poker bright-red hot, and having opened a window, apply the
poker quickly very near to the outside of a pane, and the
hand to the inside; a strong heat will be felt at the instant,
which will cease as soon as the poker is withdrawn, and may
be gain renewed, and made to cease as quickly as before.
Now, it is well known, that if a piece of glass is so much
warmed as to convey the impression of heat to the hand, it will
retain some part of that heat for a minute or more; but, in this
experiment, the heat will vanish in a moment. It will not, there-
fore, be the heated pane of glass that we shall feel, but heat which
has come through the glass, in a free or radiant state.
MITALS UNMQUALLT INTLUINCKD BY HBAT.
All metals do not conduct heat at the same rate, as may be
proved by holding in the flame of a candle at the ame time, a
piece of silver wire, and a piece of platina wire, when the silver
wire will become too hot to hold, much sooner than the platina. Or,
cut a come of each wire, tip it with wax, and place it upon a
heated plate (as a fire-horel), when the wax will melt at difrent
LIGHT AND RZAT.
Mix a little chlorate do potm with spirit of wiin a *ong
saucer; add a little sulphuric acid, and an orange vspour ill
arise and burst into fame.
INEQUALITY or BEAT IN FIRE-IRONS.
Place before abrisk fr a set of polished ire-irons, and beside
them a rough unpolished poker, such as is used in a kitchen, or
instead of a bright poker. The polished irons will remain for a
long time without becoming warmer than the temperature of the
room, because the heat radiated from the fire is all rejected, or
thrown off, by the polished surface of the irons, and none of it is
absorbed. The rough poker will, however, become speedily hot,
so as not to be used without inconvenience. Hence, the polish of
fire-irons is not merely ornamental but useful
ZXPAMSIOR or METAL BT HIAT.
Provide an iron rod, and fit it exactly into a metal ring; heat
the rod red-hot, and it will no longer enter the ring.
Observe an iron gate on a warm day, when it will shut with
difficulty; whereas, it will shut loosely and easily on a cold day.
EVAPORATION OF A METAL.
Rub a globule of mercury upon a siver spoon, and the two
metal will combine with a white appearance; heat the spoo care-
fully in the ame of a spirit lamp, when the mercury willvolatilise
and disappear, and the spoon may then be polished until it cover
LIGHT AND BEAT.
its unsal lustre: i, however, the mercury be left for some time
on the spoon, the solid texture of the silver will be destroyed
throughout, and then the silver can only be recovered by heating
it in a ladle.
A FLOATIOG METAL ON FIR1.
Throw a small piece of that marvellous substance, potassium,
into a basin of water, and it will swim upon the surface, and burn
with a beautiful light, of a red colour mixed with violet. When
moderately heated in the air, potassium takes fire, and burns with
a red light.
HEAT AND COLD ROM PLAN NEL.
Put a piece of ice into a basin, which wrap up in many folds
of flannel, and the ice may be preserved for some time by the
ICE MELTED BT AIR.
If two pieces of ice be placed in a warm room, one of them
may be made to melt much sooner than the other, by blowing on
it with a pair of bellows.
TO HOLD A HOT TEA-KETTLE ON THE HAND.
Be sure that the bottom of the kettle is well covered with soot;
when the water in it boils, remove it from the fire, and place it
upon the palm of the hand; no inconvenience will be felt, a the
soot will prevent the heat being transmitted, from the water within
and the heated metal, to the hand.
LIGHT AND HEAT. s
Make a strong solution of borax in water, and steep in it linen,
muslin, or any article of clothing; when dry, they cannot eaily
THE BURNING CIRCLE.
Light a stick, and whirl it round with a rapid motion, when its
burning end will produce a complete circle of light, although that
end can only be in one part of the circle at the same instant.
This is caused by the duration of the impression of light upon
the retina. Another example is, that during the twinkling of the
eye we never lose sight of the object we are viewing.
WATER OF DIFFERENT TIMPZRATURES IN THE IAME VTISEL.
Of heat and cold, as of wit and madness, it may be aid that
" thin partitions do their bounds divide." Thus, paint onehalf of
the surface of a tin-pot with a mixture of lamp-black and size, and
leave the other half or side, bright; fill the vessel with boiling
water, and by dipping a thermometer, or even the finger, into it
shortly after, it will be found to cool much more rapidly upon the
blackened than upon the bright side of the pot.
WARMTH OF DIPrlRENT COLOURS.
Place upon the surface of snow, as upon the window-sill, in
bright daylight or sunshine, pieces of cloth of the same sise and
quality, but of different colours, black, blue, green, yellow, and
white: the black cloth will soon melt the snow beneath it, and sink
downwards; next the blue, and then the green; the yellow but
slightly; but the snow beneath the white cloth will be as firm
as at first.
W LIOHT AND HBAT.
Us1TITUTI IOU lilts.
Put into a cup a lump of quick-lime, feh from the kiln, pour
water upon it, and the heat will be very great. A pilll of
quick-lime, if dipped in water, and shut closely into a box con-
structed for the purpose, will give out sufficient heat to warm a
room, even in very cold weather.
GAS AND STEAM.
Rn above fanciful appellation has been given to
nitrous oxide, from the very agreeable sensu-
tions excited by inhaling it. In its pure state
it destroys animal life, but loses this noxious
quality when inhaled, because it becoan
blended with the atmospheric air which 41;
meets in the lungs. This gas is made b
putting three or four drams of nitrate of ammonia, in crystals,
Into a small glass retort, which being held over a spirit-lamp, the
crystals will melt, and the gas be evolved.
Having thus produced the gas, it is to be passed into a large
bladder, having a stop-cock; and when you are desirous of exhibit-
ing its effects, you cause the person who wishes to experience them,
to first exhale the atmospheric air from the lungs, and then quickly
@a@ %NFR) @719AM
GAS AND STRAM.
placing the cock in his mouth, you turn it, and bid him inhale the
Sgs. Immediately, a sense of extraordinary cheerhfane, Afncmh
flights of imagination, an uncontrollable propensity to laughter,
and a consciousness of being capable of great muscular exertion,
supervene. It does not operate in exactly the same manner on all
persons; but in moat cases the sensation are agreeable, and have
this important difference from those produced by wine or spirituous
liquor, that they are not succeeded by any depression of mind.
TRZ LUMINOUS WAND.
Cover a long slip of wood, half way, with sulphur, by immer-
sion while in a melted state. Having prepared a jar of nitrous
oxide gas, a in preceding experiments, light the sulphur, and
plunge the wand into thejar. The ga will extinguish the flame.
Withdraw the wand, light it again, and when the flame is very
brilliant, immerse it again in the jar. It will this time burn with
great spledour, ad of a beantifl red colour.
TO MAKE CARBONIC ACID GAl.
Put about an ounce of marble in small lumps, into an eight-
ounce phial, with about an equal quantity of water; pour in a
little muriatic acid, and carbonic acid gas will be evolved.
CARBONIC ACID GAS IN WINE OR BBER VESSELS.
The apparently empty or upper part of vessel in which wine
or beer is working, is filled with this deleterious gas; for its
great weight prevents its ascent from the fermenting liquid. A
variety of striking but simple experiments may be made with the
GAS AND STEAM.
gas in this condition. Lighted paper, or a candle dipped into it,
will be immediately extinguished; and the smoke remaining in
the carbonic acid gas will render its surface visible, which may be
thrown into waves by agitation, like water. In consequence of
the great weight of the carbonic acid gas, it may be taken from
a vat of fermenting liquor, in a jug or bottle, and in the latter, if
well corked, it may be conveyed to great distances; or the gas
may be drawn out of a vessel by a cock, like a liquid.
TO EXTINGUISH FLAME WITH OAS.
The effects produced by pouring carbonic acid gas from one
vessel to another, have a very singular appearance; if a lighted
candle be placed in a jar, and the gas be poured upon it, the
flame will be extinguished in a few seconds, though the eye is
incapable of distinguishing that anything is poured out
EFFECT OF HYDROGEN ON THE VOICE.
Make a hole through a wine cork of ufficient size to admit a
smaller cork; through which make another hole, and fix it into
the larger one. Tie the corks thus fixed into the neck of a
bullock's bladder, previously exhausted of air; let a tube from a
bottle generating hydrogen pas very tightly through the aperture
in the small cork, and the gas will distend and fll the bladder.
The instant it is full, withdraw the inner cork, and either prevent
the escape of the gas by means of the thumb, or cork it closely, till
the operator is ready to breathe te ga; to do which, he should
put the open cork into his mouth, and take one inspiration, when,
on immediately speaking, his voice will be remarkably shrill. The
effect will pass off in a few seconds.
GAS AND STEAM.
Provide a piece of copper wire, about ten inches long, and fix
at one end of it a piece of wa taper: take a pint bottle of hydro-
gen, and place the mouth downwards; light the taper, introduce it
into the bottle, and the gas will take fire, and burn slowly towards
the mouth, where it is in contact with the air. It however, the
taper be passed up into the bottle, it will be extinguished; but, on
gently withdrawing it through the burning hydrogen, the wick will
be rekindled. This may be done several times in succession with
the same portion of gas.
THE OAS CANDLE.
Provide a strong glass bottle which will contain about eight
tio ounces, or half a pint, into which put a few pieces
A of sine; then mix half an ounce of sulphuric acid
With four ounces of water, and pour it into the bottle
upon the inc; fit the mouth closely with a cork,
through which put a metal tube which ends upward in
a fine opening: the mixture in the bottle will oon
eferveece, and hydrogen gas will rise through the tube.
When it has escaped for about a minute, apply a lighted
paper to the tube, and the gas will burn like a candle,
but with a pale flame. Its brightness may be increased
to brilliance, by sifting over it a small quantity of mag-
Provide a bladder, fill it with hydrogen gas, to be made as for
the lat experiment, and fit the end of a tobacco-pipe closely
into the bladder; dip the bowl of the pipe into soap and water, and,
GAB AND ITBAM.
by pressing the bladder, soap-bubbles wi be formed, lled with
hydrogen gas; which bubbles, or balloons, will rise in the air, and
keep there for some time.
GAS-LIGHT IN THE DAT-TIMI.
Light a stream of hydrogen gaM, and it wil be scarcely visible
in the day-light; but place in it a small coil of platinum wire, or
project a little oxide of since through the flame, and it will become
One of the simplest and most beautiful experiments in aerosta-
tion, is to take a turkey's maw, or stomach, properly prepared,
and to fill it either with pure hydrogen gaM, or the carburetted
hydrogen produced from coal. If the balloon be then allowed to
escape in the open air, it will ascend rapidly in the atmosphere:
but the best method of showing the experiment, is to let the
balloon of a high staircaee, and observe it ascend to the cupola or
light, where it will remain near the highest point till the escape
of the gas allow it to descend. The prepared maw for this balloon
may be purchased of any optician.
Bicarburetted hydrogen is the principal constituent of the gas
burned in the streets: it is procured from coal, and the procem
may readily be performed on a small scale. Put about two ounces
of pounded coal into an earthen retort, and fix a glass tube into
the neck, terminating in an aperture of one-fth of an inch in
diameter; heat the retort red-hot, and apply the flame of a taper
GAS AND STIAM.
to the orifio of the tube, when the gs will burn with a bright
white light, very different from that afforded by the combustion of
hydrogen; a circumstance owing to the presence of particles of
carbon in the carburet, which being intensely ignited, are highly
It is no lew strange than true, that bicarburetted hydrogen, the
substance which we so largely consume to illuminate our towns, is
ether when united to water in one proportion, and spirit when
combined with it in another; a fluid which constitutes the strength
of all wines, beer, and fermented liquors.
Into a half-pint glass bottle, put some zinc, granulated by
being melted in a ladle, and then poured gradually into water.
Add some sulphuric acid, diluted with eight parts
by weight of water. Then pass a glass tube with a
capillary bore, through a cork, which you have pre-
viously made to closely it'the bottle, and cork the
bottle well. In a short time, the atmospheric air will
be expelled, and hydrogen gas will rise through the
tube; you then apply a light, and the gas will become
ignited. If you now hold another glass tube, about
eighteen or twenty inches long, over the flame, sufi-
ciently wide to enclose the other tube very loosely (we
empeing), the little speck of flame will sport along
the larger tube, and musical sounds will be produced,
which may be varied by using other tubes of different
dimensions, and made of different materials; the wide
tubes farming the lower, and the narrow tubes the upper notes.
GAS AND STBAM.
MINIATUIU WILL o'-THN-WIOP.
Put a umall piece or two of the phosphuret olime Into a aucer
of water, when bubbles of phosphuretted hydrogen gas will rie to
the sor&ce, explode into uame, and cause a white smoke ; repre-
aenting, on a small .cale, the ignifahmu, or will o'-the-wsp, a
seen over marhy ground, or stagnant pool of water.
A light so brilliant that the eye can scarcely bear to contem-
plate it, is produced by the immersion of phophorus in oxygen
gas. To perform this experiment, you place a piece of phophorus
in a copper cup of the circumference of a sxpence, which is
fuatened to a thick piece of iron wire, attached to a cork which fit
a bottle (a in the foregoing experiment) filled with oxygen gas.
Set fire to the phosphorus, and quickly plunge it into the bottle;
when the splendour of the combustion will be surpassingly bean-
It i necessary to observe, that the beat is so excessive, that if
the piece of phosphorus in this experiment be larger than a small
pea, there will be great danger of breaking the bottle.
COMBUSTION O0 IRON IN OXYGEN GAS.
Twist a piece of fine iron wire, euh a i used by piano-forte
makers, round a eylindrically-4haped piece of wood or metal, which
will give it a spial form; or a broken watch-spring, which may be
bought for a trife of the watchmakers, will answer the same
purpose. Fate.n round one end of it some waxed cotton thread or
twine, and attach the other end to a cork, which fits a glajar or
bottle that will hold a quart, filled with oxygen ga. Having
made the wire red-hot by setting light to the thread, plunge it into
OGA AND STEAl.
thebotfle. Do not cork the bottle, but let the cork merely lay on
the mouth, and to prevent its being burned a small piece of lead
should be fastened to the bottom of it. The iron will instantly
begin to burn with great brilliancy, throwing out luminous scin-
To prevent the bottle from being broken by the sparks, a small
quantity of sand should be previously poured into it.
GLOW-WORM IN OXTGON GAS.
If a glow-worm be placed in a jar of oxygen gas, in a dark
room, it will shine with a far surpassing brilliancy to that which
it exhibits in atmospheric air.
Attach a small piece of charcoal to the end of a copper wire;
make it red-hot, and immerse it in a jar of oxygen gas. The
charcoal will born with great brilliance, throwing out splendid scin-
tillation. The bark of the wood converted into charcoal must be
selected, otherwise there will be no scintillation..
BSILLIANT COMBUSTION IN OXTOZN.
Place in a bottle of oxygen'gas a lighted taper, and it will
burn with a fame of increased brilliancy.
Extinguish the taper immediately; put it into the lame or
another bottle of oxygen, and it will be again lighted, provided a
spark remain on the wick.
Bend a piece of iron wire in a piral form, and tie on to one
end some cotton or lax; sprinkle ome flour of sulphur on it, et
it on fire, dip it into a bottle of oxygen ga, and beautiful comac*-
tims will be thrown of the wie.
091 AND STSAM.
PLANa PROM COLD MIAU.
Provide a bottle of the gea chlorine, which may be pumrch d e
ay operative chemit, and with it you may exhibit some brmlia
For example, reduce a mall piece of the metal antimony to a
very fine powder in a mortar; place some of this on a bent card,
then loosen the stopper of the bottle of chlorine, and throw in the
antimony, it will take fire spontaneously, and burn with much
splendour; thus exhibiting a cold. metal spontaneously burtia
If, however, a lmp of antimony be dropped into the chlorine,
there will be no spontaneous combustion, nor, immediate chage
but, in the course of time, the antimony will become inarused with
a white powder, and no chlorine will be found in the bottle.
Or, provide copper i fine leaves, known aa "Dteh metal;"
slightly breathe on one end of a gla rod, about ten inches long, aad
coaue one or two leaves of the metal to adhere to the damp and;
then open a bottle of chlorine, quickly plunge in the leave, whm
they will instantly take fre, and burn with a e red lght, leeitag
in the bottle a greenih-yellow solid subetanee.
A small lump of copper, or "Dutch metal," will not ham a
above, but will be slowly acted upon, like the antimony.
Immerse gold leaf in a jar of chlorine gaa, and combustion with
a beautiful green flame will take place.
PHOSPHORUS IN CHLORINE.
Pt into a defagrating spoon about four grain optosphora
ad let it down into bottle of chlorine, when the phospepu will
GOA AND STAM,
Or, fold a dip of blotting-paper into a match ve inches leog;
dip it into oil of turpentine, drain it an instant, drop it into another
bottle o chlorine, when it will burt into a lame, and deposit much
Put a little ether into a bottle of eaoutchouc, close it tightly,
Soak it in hot water, and it will become inflated to a considerable
slse. These globes may be made so thin as to be transparent
A piece of coutchouc, the sie of a walnut, has thus been ex-
tended to abell fifteen inches in diameter; and a few years since, a
caoutchouc balloon, thus made, escaped from Philadelphia, and wa
found 130 miles from that city.
TO INCREA5n TEX LIGHT OF COAL GOA.
Ly a piece of wire-gae upon the glaS chimney of a common
argand gas burner, when the fame will be enlarged to twice its
fmer dimensions, and its light fully doubled. If the experiment
be made with a common argand oil-lamp, the flame will be often
enlarged,but so dcoloured as to yield le light,
GAS ]FOM INDIAN UBBlflL
Put caoutchoucine, or the spirit distilled from caoutchouc,
or Indian rubber, into a phial, little more than efficient to cover
the bottom, and the remainder of the phial will be filled with a
beavy yapour; pour thi off the spirit into another phial, apply
to it a pice of lighted paper, and the vapour will burn with ,
OAS AND I3AM.
Let & a few drops o other into a large drinlng-gla, and
cover itwith a plate for a few minutes; during this time, the glai
willbe filled with vapour from the ether, o that,on removing the
plate, and applying apiee of lighted paper at the mouth of the gla,
the invisible vapour will take fire; thus proving how readily a vrle-
tile luid, such a ether, combines with the air.
Provide a gluss tube, brout three feet long ad half an inch in
diameter, nearly ll it with water, upon the sorface of which pour a
little coloured ether; then doee the open end of the tube cardly
with the palm of the hand, invert it in aban of water, and rest
the tube against the wall: the ether wiM rie through the water t
the upper end of the tube; pour a littlehot water oer the tube,
and it will oon cae the ether to boil within, and it vapour may
thus be mde to drivnearly al theater out of th tube into the
bain; K however, you then cool the tube by pouring cold water
orer it, the vaporied other will again become a liquid, and fdoe
upon the after a before
GAS ILOM TBR UNION 01 MITALS.
Nearly in a wine-glas with diluted sulphuric acid, and place
Sit wire of silver and another of sin, taking care that they do
not touch each other; when the ino will be changed by the add,
but the iver will remain inert. Bt, cause the upper ends d
the wires to touch each other, and a stram of ga will iss"