Part 12

Immerse a slip of copper in dilute nitric acid, and it will be soon corroded and dissolved; but, if a slip of zinc be immersed with the copper, the zinc will be dissolved, and the copper remain unaltered and uninjured.

LIGHT FROM THE DIAMOND.

Expose a fine diamond to the sunbeams, and carry it into a dark room, when it will exhibit phosphorescence: and it has been stated that such diamonds as do not display this peculiarity, may be made to do so by dipping them into melted borax.

The diamond becomes phosphorescent also when fixed to the prime conductor of an electrical machine, and a few sparks may be taken from it. It likewise becomes electric by friction; and the Hon. Mr. Boyle obtained electric gleams by rubbing two diamonds together in the dark.

TO BREAK A STONE WITH A BLOW OF THE FIST.

Select two stones from three to six inches long, and about half as thick; lay one flat on the ground, on which place one end of the other, raising the reverse end to an angle of forty-five degrees, and just over the centre of the stone (with which it must form a T,) supporting it in that position by a piece of thin twig or stick, one, or one and a half inch long; if the raised stone be now smartly struck about the centre, with the little finger side of the fist, the stick will give way, and the stone will be broken to pieces: the stones must be laid so as not to slip, otherwise the experiment will fail.

MIMIC FROST-WORK.

Fasten a sprig of fresh rosemary, or any similar shrub, to the inside of a small bandbox, near the top; heat a thick tile, and sprinkle it with gum benzoic, and immediately place the bandbox over it, when the acid will be sublimed by the heat, and will condense in a white vapour upon the green plant, giving it the appearance of being covered with hoarfrost.

TO MELT LEAD IN A PIECE OF PAPER.

Wrap up a very smooth ball of lead in a piece of paper, taking care that there be no wrinkles in it, and that it be everywhere in contact with the ball; if it be held in this state, over the flame of a taper, the lead will be melted without the paper being burnt. The lead, indeed, when once fused, will not fail in a short time to pierce the paper, and run through.

HYDROSTATIC BALANCE.

Provide a pair of scales, in one of which place a tumbler filled with water, and poise it by placing weights in the opposite scale; then hold in the tumbler a block of wood, or any substance nearly the size of the tumbler, but so that it shall not touch the sides or bottom; when, although nearly the whole of the water will have to run over the sides, and only a spoonful may remain, the scales will continue balanced; and all this without regard to the weight of the body you plunge into the water, taking care to hold it entirely clear of the tumbler, so that it touch it nowhere; for the effect will be the same if what you plunge in be scooped hollow and made water-tight. A bladder blown up, tied fast, and held down in the water, so as to leave only a spoonful of water surrounding it, will keep the scales balanced just as well as a block of lead of the same size.

METALLIC REDUCTION.

Mix a little red lead with some powdered charcoal, and with the mixture fill the bowl of a tobacco-pipe; set it over a common fire, and in about twenty minutes the lead will be found reduced to its metallic state.

SIMPLE ELECTRICITY.

ELECTRICAL ATTRACTION AND REPULSION.

Rub a piece of amber, a stick of red sealing-wax, or a smooth glass tube, smartly upon the sleeve of a coat, or any other dry woollen substance, and it will attract to itself bits of straw, paper, fragments of gold leaf, or any small and light bodies. The amber, wax, or glass, is then said to be excited, and the attractive power thus developed, is called electrical attraction.

Select a clean and dry downy feather, and suspend it from a beam by a long thread of white silk; to be used in the following experiments:

Provide a glass tube, about three feet long and three quarters of an inch diameter; wipe it dry, and rub it gently with a warm silk handkerchief; then apply the tube to the feather, and it will _attract_ it; withdraw the tube gently, apply it again, and the feather will be repelled for a time, but then attracted, and then again repelled. In this case, the feather having received electricity from the glass, is repelled by it; for bodies similarly electrified repel each other.

Fold a silk handkerchief, warm it, and with it rub the tube; apply it to the feather, and it will first attract and then repel it; when the feather has just been repelled by the silk, apply the tube, and the feather will be attracted. The handkerchief must be folded so thickly as to keep the hand as far as possible from the glass tube.

Roll up flannel thickly, rub it with sealing-wax, and the roll will by turns attract and repel the feather; when thus repelled, apply the excited wax, and it will instantly attract the feather.

When the atmosphere is dry, take in one hand a rod of glass and in the other a stick of sealing-wax, and rub them against silk or worsted; with one of them approach a bit of gold-leaf, floating in the air, it will first attract and then repel it. When the gold has just been repelled, approach it with the other rod, and it will be immediately attracted; and this alternate attraction and repulsion may be strikingly displayed by placing the two excited rods at a small distance asunder, with the gold leaf between them.

ALCHEMICAL ELECTRICITY.

Nearly fill a wine-glass with a weak solution of blue vitriol in water, and place in it the blade of a knife and a small silver spoon; the knife will soon acquire a copper coating, but the spoon will remain bright until it is touched with the blade of the knife, when it will also become plated with copper.

THE ELECTRIC BALLS.

Provide two small balls of equal size; both made of gum-lac, and cover one with gold leaf. Suspend these balls from a beam by fine white silk threads, at a little distance from each other, so as to allow a comparison of their motions. Then rub a stick of red sealing-wax upon any woollen substance, or warm it at the fire, and present it to the balls; when it will be at once seen that the gilt ball, which readily admits of the transfer of electricity from one side to the other, will be sooner and more powerfully attracted than the other ball, which allows of no motion in its electricity. The latter ball will, however, by slow degrees be feebly attracted, and may, at length, be made to adhere for a considerable time to the sealing-wax.

THE ELECTRIC DANCE.

Lay on a table small pieces of paper or cotton, feathers, or gold-leaf; then rub with a silk handkerchief a glass tube, hold it parallel to the table, and the several pieces will be alternately attracted and repelled, and a kind of electrical dance will be kept up.

If to the further end of the tube you hang a brass ball, by a thread of linen, hemp, or metallic wire, the ball will participate in the magic power of the rubbed tube; but if the ball be suspended by a cord of silk, worsted, or hair, or be attached by wax or pitch, the attractive and repulsive properties of the rod will not pass into the ball.

ELECTRIC LIGHT.

Shake a barometer in a dark room, and light will be produced in the empty part of it by the friction of the quicksilver electrifying the glass tube. Even the friction of air upon glass is attended by electricity, as has been found by blowing upon a dry plate of glass with a pair of bellows.

ELECTRIC LIGHT FROM BROWN PAPER.

Provide a piece of thick brown paper, thoroughly dry and warm; rub the paper briskly in a dark room, and there will dart forth flashes of electric light to the fingers, to a key, or to any other conductor that may be presented to it.

Heat a small portion of sulphate of quinine in a spoon over the flame of a lamp, and it will become luminous and highly electrical.

SUDDEN PRODUCTION OF LIGHT.

Take a piece of dry and warm wood into a dark room, suddenly rend it asunder, and a flash of light will be perceived. The same effect may likewise be produced by suddenly snapping asunder a stick of sealing-wax in the dark.

Or, break a Prince Rupert’s drop, and electrical light will pervade the whole, so that its form will be distinctly visible in the dark. The light will appear, even if the experiment be made under water.

ELECTRICITY OF THE CAT.

Place your left hand upon the throat of the cat, and, with the middle finger and the thumb, press slightly the bones of the animal’s shoulders; then, if the right hand be gently passed along the back, perceptible shocks of electricity will be felt in the left hand. Shocks may also be obtained by touching the tips of the ears after rubbing the back. If the colour of the cat be black, and the experiment be made in a dark room, the electric sparks may be very plainly seen.

Very distinct discharges of electricity may also be obtained by touching the tips of the ears, after applying friction to the back; and the same may be obtained from the foot. Placing the cat on your knees, apply your right hand to the back; the left fore paw resting on the palm of your left hand, apply the thumb to the upper side of the paw, so as to extend the claws, and, by this means, bring your fore-finger into contact with one of the bones of the leg, where it joins the paw; when, from the knob or end of this bone, the finger slightly pressing on it, you may feel distinctly successive shocks, similar to those obtained from the ears.

It is, perhaps, unnecessary to add, that, in order to this experiment being conveniently performed, the experimenter must be on good terms with the cat.

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Transcriber’s Notes:

Obvious punctuation errors repaired. Varied hyphenation was retained.

Page x, “Phenakisticope” changed to “Phenakistiscope” and “Stoboscope” changed to “Stroboscope” (The Phenakistiscope or Stroboscope) This same change was also made on page 34 in all-capitals (THE PHENAKISTISCOPE, OR STROBOSCOPE)

Page xii, “110” changed to “112” for the entry of “The Mysterious Circles” to match location in text.

Page 3, “loose” changed to “lose” (it will lose all)

Page 44, the original instructions for tuning a guitar, read (like an inverted Λ) As this would just be a “v” and would not be like a saddle, the instruction was changed to (like an inverted v, Λ)

Page 54, “versá” changed to “versâ” (red, and _vice versâ_)

Page 60, “widows” changed to “windows” (glasses in druggists’ windows)

Page 82, word “a” removed from text. Original read (small a piece of lead)

Page 82, “cut” changed to “out” (throwing out luminous)

Page 83, word “be” removed from text. Original read (antimony will be become)

Page 83, “Duch” changed to “Dutch” (copper, or “Dutch metal,”)

Page 98, “FRAME” changed to “FLAME” (COMBUSTION WITHOUT FLAME)

Page 100, “fell” changed to “feel” (will feel _warmth_)

Page 100, “fully” changed to “full” (cup nearly full of water)

Page 111, word “a” added to text (jar with a bladder)

Page 111, “amadon” changed to “amadou” (a scrap of amadou)

Page 113, “have” changed to “has” (tube passes has)

Page 114, “smells” changed to “swells” (the moisture swells the)

Page 114, “increase” changed to “increases” (threads, and increases)

Page 116, “as so” changed to “so as” (so as to resemble)

Page 127, “befow” changed to “below” (below the ring)

Page 132, “pale” changed to “pail” (pail of water on)

Page 136, “hankerchief” changed to “handkerchief” (midst of the handkerchief)

Page 156, “skaiter” changed to “skater” (as a skater does)