Chapter V: Part 5

You profess that you will make a sixpence appear to pass through the table. To perform this feat, you must have a handkerchief, in one corner of which is sewed a sixpence.—Take it out of your pocket, and ask one of the company to lend you a sixpence, which you must seem to carefully wrap up in the middle of the handkerchief, but instead of which, you keep it in the palm of your hand, and in its stead, wrap up the corner in which the other sixpence is sewed, in the midst of the handkerchief, and bid the person from whom you borrowed the sixpence, feel that it is there. You then lay it under a hat upon the table, take a glass in the hand in which you have concealed the sixpence, and hold it under the table. Give three knocks upon the table, crying “Presto! come quickly!” Then drop the sixpence into the glass; bring the glass from under the table, and exhibit the sixpence to the spectators. You lastly take the handkerchief from under the hat, and shake it, taking care to hold it by the corner in which the sixpence was sewed.

THE VANISHING SIXPENCE.

Having previously stuck a small piece of white wax on the nail of your middle finger, lay a sixpence on the palm of your hand, and addressing the company, state that it will vanish at the word of command. “Many persons,” you observe, “perform this feat, by letting the sixpence fall into their sleeve; but to convince you that I shall not have recourse to any such deception, I will turn up my cuffs.” You then close your hand, and bringing the waxed nail in contact with the sixpence, it will firmly adhere to it. You then blow your hand, and cry “Begone!” and suddenly opening it, and exhibiting the palm, you show that the sixpence has vanished. If you borrow the sixpence of any of the company, take care to rub off the wax, before you restore it to the owner.

TO MAKE A SIXPENCE BALANCE AND SPIN ON ITS EDGE, ON THE POINT OF A NEEDLE.

Procure a common wine-bottle, two forks, two corks, a needle, a sixpence, and a penknife. Having corked the bottle, force the eye of the needle into the cork perpendicularly, leaving more than half the needle sticking up. You next cut a small slit with the penknife in the centre of the bottom of the second cork, into which you insert the sixpence edgewise; then stick the forks into the upper cork, and, with a steady hand, place the edge of the sixpence on the point of the needle, and it will immediately find its balance. You may now take the upper cork between the finger and thumb, and spin it round as fast as you please, as the sixpence will not fall off. When it goes slow, hit one of the forks with your finger as it goes round, to increase its velocity.

THE MULTIPLYING COIN.

Let a tumbler be half-filled with water; put a sixpence in it; and holding a plate over the top, turn the glass upside down. The sixpence will fall down on the plate, and appear to be a shilling; while at the same time a sixpence will seem to be swimming in the water. If a shilling is put in the glass, it will have the appearance of a quarter of a dollar and a shilling; and if a quarter of a dollar were put in, it would seem to be half a dollar and a quarter of a dollar.

MAGIC RAT TRAP.

Prepare a pasteboard circle, upon one side of which draw a figure of a cage, and on the other side that of a rat. Near the outer edge of the circle fasten two strings opposite each other. So that they may be held between the fore finger and thumb in such manner that the circle may be made to revolve rapidly. When it is set in motion the transition is so quick, that it presents the appearance of a rat in the cage.

TO SHOW THE VELOCITY OF MOTION.

Take a long hollow stalk or reed, suspend it horizontally by two loops of single hairs; by striking it with a sharp quick stroke at a point nearly in the centre, between the hairs, it may be cut through without breaking either of them. The hairs in this case would have been ruptured, if they had partaken of the force applied to the stalk; but the division of the latter being affected before the impulse could be propagated to the hairs, they must consequently remain unbroken.

A smart blow, with a slight wand or hollow reed on the edge of a glass tumbler, would break the wand, without injury to the glass.

Lay a small piece of money upon a card placed over the mouth of a glass tumbler, and resting upon the rim of the glass. The card may be withdrawn with such speed and dexterity, that the piece of money will not be removed laterally, but will drop into the glass.

THE EXPLODING BUBBLE.

If you take up a small quantity of melted glass with a tube, (the bowl of a common tobacco pipe will do,) and let a drop fall into a vessel of water, it will chill and condense with a fine spiral tail, which being broken, the whole substance will burst with a loud explosion, without injury either to the party that holds it, or him that breaks it; but if the _thick_ end is struck even with a hammer, it will not break.

THE MAGIC PICTURE.

Take two level pieces of glass, (plate glass is the best,) about three inches long and four wide, exactly of the same size; lay one on the other, and manage to leave a space between them by pasting a piece of card, or two or three small pieces of thick paper at each corner.

Join these glasses together at the edge by a composition of lime slacked by exposure to the air, and white of an egg. Cover all the edges of these glasses with parchment or bladder, except at one end, which is to be left open to admit the following composition:

Dissolve by a slow fire six ounces of hog’s-lard, with half an ounce of white wax; to which you may add an ounce of clear linseed oil.

This must be poured in its liquid state, and before a fire, between the glasses, by the space left in the sides, and which you are then to close up. Wipe the glasses clean, and hold them before the fire, to see that the composition will not run out at any part.

Then fasten with gum a picture or print, painted on very thin paper, with its face to one of the glasses, and if you like, you may fix the whole in a frame.

While the mixture between the glasses is cold, the picture will be quite concealed, but become transparent when held to the fire; and as the composition cools, it will gradually disappear.

ARTIFICIAL LIGHTNING.

Provide a tin tube that is larger at one end than it is at the other, and in which there are several holes. Fill this tube with powdered resin; and when it is shook over the flame of a torch, the reflection will produce the exact appearance of lightning.

THREE OBJECTS, DISCERNIBLE ONLY WITH BOTH EYES.

If you fix three pieces of paper against the wall of a room at equal distances, at the height of your eye, placing yourself directly before them, at a few yards’ distance, and close your right eye, and look at them with your left, you will see only two of them, suppose the first and second; alter the position of your eye, and you will see the first and third; alter your position a second time, you will see the second and third, but never the whole three together; by which it appears, that a person who has only one eye can never see three objects placed in this position, nor all the parts of one object of the same extent, without altering the situation of his eye.

TO TELL BY A WATCH DIAL THE HOUR WHEN A PERSON INTENDS TO RISE.

The person is told to set the hand of his watch at any hour he pleases, which hour he tells you; and you add in your own mind 12 to it. You then desire him to count privately the number of that addition on the dial, commencing at the next hour to that at which he intends to rise, and including the hour at which he has placed the hand; which will give the answer; for example,

A intends to rise at 6 (this he conceals to himself;) he places the hand at 8, which he tells B, who, in his own mind, adds 12 to 8, which make 20. B then tells A to count 20 on the dial, beginning at the next hour to that at which he proposes to rise; which will be 7, and counting backwards, reckoning each hour as 1, and including in his addition the number of the hour the hand is placed at, the addition will end at 6, which is the hour proposed; thus,

The hour the hand is placed at is 8

The next hour to that which A intends to rise at is 7,
which counts for 1

Count back the hours from 6, and reckon them at 1 each,
there will be 11 hours, viz. 4, 3, 2, 1, 12, 11, 10, 9, 8, 7, 6, 11
——
Making 20

TO MAKE A RING SUSPEND BY A THREAD, AFTER THE THREAD HAS BEEN BURNED.

Soak a piece of thread in urine, or common salt and water. Tie it to a ring, not larger than a wedding ring. When you apply the flame of a candle to it, it will burn to ashes, but yet sustain the ring.

TO MELT A PIECE OF MONEY IN A WALNUT-SHELL, WITHOUT INJURING THE SHELL.

Bend any thin coin, and put it into half a walnut-shell; place the shell on a little sand, to keep it steady. Then fill the shell, with a mixture made of three parts of very dry pounded nitre, one part of flowers of sulphur, and a little saw-dust well sifted. If you then set light to the mixture, you will find, when it is melted, that the metal will also be melted in the bottom of the shell, in form of a button, which will become hard when the burning matter round it is consumed; the shell will have sustained very little injury.

THE MAGICAL MIRRORS.

Make two holes in the wainscot of a room, each a foot high and ten inches wide, and about a foot distant from each other. Let these apertures be about the height of a man’s head, and in each of them place a transparent glass in a frame, like a common mirror.

Behind the partition, and directly facing each aperture, place two mirrors, inclosed in the wainscot, in an angle of forty-five degrees.[A] These mirrors are each to be eighteen inches square: and all the space between them must be enclosed with pasteboard painted black, and well closed, that no light can enter; let there be also two curtains to cover them, which you may draw aside at pleasure.

When a person looks into one of these fictitious mirrors, instead of seeing his own face, he will see the object that is in front of the other; thus, if two persons stand at the same time before these mirrors, instead of each seeing himself, they will reciprocally see each other.

There should be a sconce with a lighted candle, placed on each side of the two glasses in the wainscot, to enlighten the faces of the persons who look in them, or the experiment will not have so remarkable an effect.

[A] That is, half-way between a line drawn perpendicularly to the ground and its surface.

THE ENCHANTED BOTTLE.

Fill a glass bottle with water to the beginning of the neck; leave the neck empty, and cork it. Suspend this bottle opposite a concave mirror, and beyond its focus, that it may appear reversed. Place yourself still further distant from the bottle; and instead of the water appearing, as it really is, at the bottom of the bottle, the bottom will be empty, and the water seen at the top.

If the bottle be suspended with the neck downwards, it will be reflected in its natural position, and the water at the bottom, although, in reality, it is inverted, and fills the neck, leaving the bottom vacant. While the bottle is in this position, uncork it, and let the water run gradually out: it will appear, that while the real bottle is emptying, the reflected one is filling. Care must be taken that the bottle is not more than half or three parts full, and that no other liquid is used but water, as in either of these cases, the illusion ceases.

THE ARMED APPARITION.

If a person with a drawn sword place himself before a large concave mirror, but further from it than its focus, he will see an inverted image of himself in the air, between him and the mirror, of a less size than himself. If he steadily present the sword towards the centre of the mirror, an image of the sword will come out from it, point to point, as if to fence with him; and by his pushing the sword nearer, the image will appear to come nearer to him and almost to touch his breast. If the mirror be turned 45 degrees, or one-eighth round, the reflected image will go out perpendicular to the direction of the sword presented, and apparently come to another person placed in the direction of the motion of the image, who, if he be unacquainted with the experiment, and does not see the original sword, will be much surprised and alarmed.

TO EXTRACT THE SILVER OUT OF A RING, THAT IS THICK GILDED, SO THAT THE GOLD MAY REMAIN ENTIRE.

Take a silver ring that is thick gilded. Make a little hole through the gold into the silver; then put the ring into aqua-fortis, in a warm place: it will dissolve the silver, and the gold will remain whole.

CURIOUS EXPERIMENT WITH A GLASS OF WATER.

Saturate a certain quantity of water in a moderate heat, with three ounces of sugar; and when it will no longer receive that there is still room in it for two ounces of salt of tartar, and after that for an ounce and a drachm of green vitriol, nearly six drachms of nitre, the same of salammoniac, two drachms and a scruple of alum, and a drachm and a half of borax.

A LUMINOUS BOTTLE, WHICH WILL SHOW THE HOUR ON A WATCH IN THE DARK.

Throw a bit of phosphorous, of the size of a pea, into a long glass phial, and pour boiling oil carefully over it, till the phial is one-third filled. The phial must be carefully corked, and when used should be unstopped, to admit the external air, and closed again. The empty space of the phial will then appear luminous, and give as much light as an ordinary lamp. Each time that the light disappears, on removing the stopper it will instantly re-appear. In cold weather the bottle should be warmed in the hands before the stopper is removed. A phial thus prepared may be used every night for six months.

RUSES.

THE WONDERFUL HAT.

Place three pieces of bread, or other eatable, at a little distance from each other on a table, and cover each with a hat; you then take up the first hat, and removing the bread, put it into your mouth, and let your company see that you swallow it; then raise the second hat, and eat the bread which was under that, and do the same with the third. Having eaten the three pieces, give any person in company liberty to choose under which hat he would wish those three pieces of bread to be; when he has made choice of one of the hats, put it on your head, and ask him if he does not think that they are under it.

TO BRING A PERSON DOWN UPON A FEATHER.

This is a practical pun:—You desire any one to stand on a chair or table, and you tell him that, notwithstanding his weight, you will bring him down upon a feather. You then leave the room, and procuring a feather from a feather-bed, you give it to him, and tell him you have performed your promise,—that you engaged to bring him _down_ upon a feather, which you have done; for there is the feather, and, if he looks, he’ll find _down_ upon it.

THE APPARENT IMPOSSIBILITY.

You profess yourself able to show any one what he never saw, what you never saw, and what nobody else ever saw, and which, after you two have seen, nobody else ever shall see.

After requesting the company to guess this riddle, and they have professed themselves unable to do so, produce a nut, and having cracked it, take out the kernel, and ask them if they have ever seen that before; they will of course answer, No; you reply, neither have I, and I think you will confess that nobody else has ever seen it, and now no one shall ever see it again; saying which, you put the kernel into your mouth and eat it.

AN OMELET COOKED IN A HAT, OVER THE FLAME OF A CANDLE.

You ask the company if they would like an omelet cooked; then you break four eggs in a hat, place the hat for a short time over the flame of a candle, and shortly after produce an omelet, completely cooked, and quite hot.

Some persons would be credulous enough to believe that by the help of certain ingredients you had been enabled to cook the omelet without fire; but the secret of the trick is, that the omelet had been previously cooked and placed in the hat, but could not be seen, because the operator, when breaking the eggs, placed it too high for the spectators to observe the contents. The eggs were empty ones, the contents having been previously extracted, by being sucked through a small aperture, but to prevent the company from suspecting this, the operator manages, as if by accident, to let a full one fall on the table, which breaking, induces a belief that the others are also full.

THE IMPOSSIBLE OMELET.

You produce some butter, eggs, and other ingredients for making an omelet, together with a frying-pan, in a room where there is a fire, and state, that the cleverest cook will not be able to make an omelet with them. The wager is won by having previously caused the eggs to be boiled very hard.

GO IF YOU CAN.

You tell a person that you will clasp his hands together in such a manner, that he shall not be able to leave the room without unclasping them, although you will not confine his feet, or bend his body, or in any way oppose his exit.

The trick is performed by clasping the party’s hands round the pillar of a large circular table or other bulky article of furniture, too large for him to drag through the doorway.

THE FIGURE PUZZLE.

You assert that you can prove the half of nine to be either four or six; and the half of twelve to be seven. To make this manifest you have only to draw a nine or a twelve in numerals, and fold the paper across the middle, as in the margin.

THE VISIBLE INVISIBLE.

You tell the company that you will place a candle in such a manner that every person in the room, except one, shall see it; yet you will not blindfold him, nor in any way restrain his person, or offer the least impediment to his examining or going to any part of the room he pleases. This trick is accomplished by placing the candle on the party’s head; but it cannot be performed if a looking-glass is in the room, as that will enable him to turn the laugh against you.

THE DOUBLE MEANING.

Place a glass of any liquid upon the table, put a hat over it, and say: “I will engage to drink the liquid under that hat, and yet I’ll not touch the hat.” You then get under the table, and after giving three knocks, you make a noise with your mouth as if you were swallowing the liquid. Then getting from under the table, you say: “Now, gentlemen, be pleased to look.” Some one, eager to see if you have drunk the liquid, will raise up the hat, when you instantly take the glass, and drink the contents, saying: “Gentlemen, I have fulfilled my promise. You are all witnesses that _I_ did not touch the hat.”

QUITE TIRED OUT.

You undertake to make a person so tired, by attempting to carry a small stick out of the room, as to be unable to accomplish it, although you will add nothing to his burthen, nor lay any restraint upon his personal liberty. To perform this manœuvre, you take up the stick, and cutting off a very small sliver, you direct him to carry it out of the room, and return for more; concluding by telling him, that you mean him to perform as many similar journeys as you can cut pieces off the stick. As this may be made to amount to many thousands, he will of course gladly give up the undertaking.

SOMETHING OUT OF THE COMMON.

Having picked a stick or stone off a common, you tell a person that you are about to show him something which will surprise him,—something, in fact, _quite out of the common_. Having thus excited his curiosity, you produce the stick or stone, or whatever else you may have picked up, which of course he will examine very intently, and at length observe, that he sees nothing extraordinary in it. “That may be,” you reply, “and yet, I assure you, that it is really something out of the common.” This will, no doubt, set him upon a fresh examination, which will naturally end in his asking for an explanation. This you give, by telling him that “though not _uncommon_, it is _out of the common_, for it is _out of —— Common_;” and no doubt, the company present will indulge in a hearty laugh at the querist’s expense.

TO RUB ONE SIXPENCE INTO TWO.

Previously wet a sixpence slightly, and stick it to the under edge of a table, (without a cover,) at the place where you are sitting. You then borrow a sixpence from one of the company, and tucking up your sleeves very high, and opening your fingers, to show that you have not another concealed, rub it quickly backwards and forwards on the table, with your right hand, holding your left under the edge of the table to catch it. After two or three feigned unsuccessful attempts to accomplish your object, you loosen the concealed sixpence with the tips of the fingers of the left hand, at the same time that you are sweeping the borrowed sixpence into it; and rubbing them a little while together in your hands, you throw them both on the table.

MAGIC CIRCLE.

You tell a person you will place him in the centre of a room, and draw a circle of chalk round him, which shall not exceed three feet in diameter, yet out of which he shall not be able to leap, though his legs shall be perfectly free. When the party has exhausted his ingenuity in trying to discover by what means you can prevent his accomplishing so seemingly easy a task, you ask him if he will try, and on his assenting, you bring him into the middle of the room, and having requested him to button his coat tightly, you draw with a piece of chalk, a circle round his waist, outside his coat, and tell him to jump out of it!

It will greatly improve this trick if the person be blindfolded, as he will not be aware of the mode of performing it till the bandage is removed, provided his attention be diverted while you are drawing the line round him.

ILLUSIONS OF TOUCH.

APPLY the points of a pair of compasses, distant from each other one or two lines, to the cheek, just before the ear; then move them successively to several other parts of the cheek, and you will find, on approaching the mouth, that the points will appear to recede from each other; this effect being produced by the great difference of the sense of touch in these parts, It is a general law, that in the more sensitive portions of the skin, any two points appear to be further asunder from each other, than points of equal distance appear to be to a less sensitive portion. The same experiments may be made by holding together the extremities of the fore-finger and thumb, and then passing the tips of both in a line from the ear to either the upper or the under lip; as they approach the latter, they will feel to the cheek as if they were becoming more and more distant from each other.

If the skin be touched with the points of a pair of compasses, one inch asunder, the person so touched, while he shuts his eyes, will instantly be aware that his skin is touched in two places; but by continually drawing the two points closer, a degree of nearness may be reached at which the person will imagine his skin to be touched by only one body: he will, however, describe this body, or the compasses, to be a little longer in one direction than another; and it appears that this difference of length corresponds with the distance between the two points of the compasses. When these points are brought still nearer together, the inequality will no longer be felt, and the person will fancy he is being touched by one body only.

Handle a pea: it is _one_—place it between the first and second fingers of the right hand, in their natural position, and you will still feel the pea but as _one_. Then cross the two fingers, bringing the second over the first, and place the pea in the fork between them, so as to feel the left side of the pea with the right side of the second finger, and the right with the left of the first The impression will then be that you have _two_ peas touching the fingers, especially if the eyes be shut, and the fingers be placed by another person. The illusion will be equally strong if the two fore-fingers of both hands be crossed, and the pea placed between them.

ILLUSION OF THE TASTE.

If the nose be held tightly while you are eating cinnamon you will perceive scarcely any difference between its flavour and that of a deal shaving.

THE GENERAL BLEACHER.

Provide some strong chloride of lime, soak in it strips of printed cotton; take them out, dry them, and you will find them very white, but very rotten, slitting and dropping into holes upon the slightest touch.

The dazzling whiteness of paper is caused by bleaching it with chloride of lime. Thus, if you write on printing paper with common ink, it will fade, because the chloride will destroy the colouring matter of writing ink. It will not, however, change printing ink, as that owes its blackness to charcoal, which is a singularly permanent substance. Blot over a printed page with common writing ink, wash it with chloride of lime, when the blots will disappear, and leave the printing unchanged.

INFLUENCE OF COLOURED GLASS ON BULBOUS ROOTS.

Put a bulb, as a hyacinth, narcissus, &c., into a white glass, and another into a purple glass: the latter will grow faster than the former; and, if a pinch of salt, or a piece of nitre, be put into the water whenever it is changed, the brightness of the colour of the flower will be considerably heightened.

THE SPINNING-TOP “ASLEEP.”

Spin a top, and it will for some time stand “asleep,” as it is called in the parlance of the play-ground. The cause is thus explained by Dr. Arnot, in his valuable _Elements of Physics_: “While the top is perfectly upright, its point being directly under its centre, supports it steadily, and although turning so rapidly, has no tendency to move from the place; but, if the top incline at all, the _side_ of the peg, instead of the very _point_, comes in contact with the floor, and the peg then becomes a little wheel or roller, advancing quickly, and, with its touching edge, describing a curve somewhat as a skater does, until it becomes directly under the body of the top, as before. It thus appears that the very fact of the top inclining causes the point to shift its place, so that it cannot rest until it come again directly under the centre of the top.”

TO JUDGE OF WEIGHTS.

Persons accustomed to estimate weights by poising them in their hands, will distinguish perfectly between two, only differing by a thirtieth part. In comparing two weights, poise one and then instantly the other, _in the same hand_; the few seconds of time that pass between the poising of the two weights will not prevent their accurate comparison. The interval may amount to twenty seconds, yet a just estimate may still be made; but when it amounts to forty seconds, all accuracy will be lost.

QUICKSILVER AND OIL UNITED.

Let fall a very small drop of oil upon a large drop of mercury, and the latter will become enlarged. This phenomenon is attributed to a combination of the oil with the mercury, which produces a compound, the attraction of which is less strong than that of pure mercury.

TO DISSOLVE THE SODA IN GLASS.

Glass consists of sand, carbonate of soda, and red lead, heated together. If water be poured into a glass vessel, neither of the ingredients will be affected by it; but, if the glass be reduced to a fine powder, and water be poured on it, the soda will instantly be dissolved.

Or, moisten, with water a piece of tumeric, or test-paper, drop on it a little powdered glass, and the soda in it will change the yellow paper to brown.

WATERPROOF PAPER.

Make a solution of caoutchouc in caoutchoucine, plunge into it, once or twice, unsized paper, and dry it by a gentle heat. It may then be used as writing paper, and will resist all humidity; and small vessels made of it will even contain water.

TO DISSOLVE GOLD OR PLATINUM.

Mix a little nitric acid with half the quantity of muriatic acid, into which put the metal for solution.

Or, pour a little aqueous solution of chlorine into a small glass, and put in a bit of pure gold leaf; stir it with a glass rod, and the gold will dissolve. Thus gold, which cannot be dissolved in nitric, sulphuric, or other strong acids, will quickly disappear in water, with a little chlorine in solution.

COLDER THAN ICE.

Mix common salt with pounded ice or snow, and they will run into brine, which will be much colder than the ice or snow.

CONTRA-CRYSTALLIZATION.

Dissolve two ounces of nitre and three of Glauber salts in five ounces of warm water; fill two bottles with the solution, into one of which put a crystal of nitre, and into the other a crystal of Glauber salts; place both bottles in ice-cold water, when nitre only will crystallize in the one and Glauber salts in the other.

ONE AND ONE DO NOT MAKE TWO.

Mix a wine-glass full of sulphuric acid with a wine-glass full of water, cautiously; and, on re-measuring the mixture, it will not be found sufficient to re-fill both glasses.

TO COPY WRITING INSTANTLY.

Add a little sugar to ink, with which write the letter to be copied; then lay a sheet of thin unsized paper, damped with a sponge, on the writing; pass lightly over it a flat iron, very moderately heated, and a reverse impression of the writing will be accurately taken off.

THE RIVAL DIALS.

Fix two pendulum clocks to the same wall, or lay two watches upon the same table, and they will take the same rate of going, though they would vary in that rate if they were placed in separate apartments. Indeed, it has been observed, that the pendulum of one clock will even stop that of the other, and that the stopped pendulum will, after a certain time, go again, and, in its turn stop the other pendulum.

TO SPIN INDIAN RUBBER.

Dissolve a small piece of Indian rubber in a little caoutchoucine, and put a drop or two of the solution upon a looking-glass or window-pane; touch it lightly with a dry piece of Indian rubber, quickly draw out a fine thread, which attach to a card, and wind off as silk.

INDELIBLE WRITING.

As the art of man can unmake whatever his ingenuity can make, we have no right to expect an indelible ink; however, an approximation to it may be made as follows: make a saturated solution of indigo and madder in boiling water, in such proportions as to give a purple tint; add to it from one-sixth to one-eighth of its weight of sulphuric acid, according to the thickness and strength of the paper to be used. Write with this ink, and expose the paper to a gradual heat from the fire, when the characters will be completely black, the letters being burnt in and charred by the sulphuric acid. If the acid has not been used in sufficient quantity to destroy the texture of the paper, and reduce it to the state of tinder, the colour may be discharged by washing it with a strong solution of oxalic acid in water. When the full proportion of acid has been employed, crumple and rub the paper, and the charred letters will fall out; then by placing a black ground behind the letters, they may be preserved, and thus a species of indelible writing may be procured, the letters being, as it were, stamped out of the paper.

VEGETABLE ANATOMY.

Soak any part of a plant in nitric acid for a short space of time, and all power of cohesion will be lost by the vessels, which will become transparent, and be easily separable from each other by gentle dissection. So complete will be the effect, that even the most delicate cells of the cellular tissue will become disengaged from each other, and may be examined singly with perfect ease. This discovery will enable persons who have not compound microscopes, and delicate directing instruments, to anatomize plants with facility.

TO TELL WHAT O’CLOCK IT IS BY THE MOON.

This may be calculated by the shadow which the moon casts upon a sun-dial, it being only necessary to know the moon’s age, which may be found in an almanack. If the new moon happens in the morning, this day is taken into the account; but if it happens after noon, the following day is counted the first. The moon’s age is to be multiplied by four and divided by five. The quotient must either be added to the hour, which the shadow indicates on the sun-dial, and the sum will give the time sought; or subtract from the quotient the hour shown by the moon upon the dial, and the remainder will give the hour sought. The first is to be done when the shadow falls on an hour of the afternoon, and the latter when it falls upon an hour of the forenoon. The following are examples:

1st. Suppose the moon to be ten days old, and the shade cast by the moon upon the sun-dial to be at half-past two; or, that the shadow cast by the moon falls on the place at which the shadow cast by the sun stands at half-past two;—what o’clock was it then? The answer is calculated as follows:—The moon’s age, 10 days × 4 = 40 40/5 = 8. Eight, therefore, is the time when the moon was in the meridian, and 8 + 2½ = 10½, or half-past ten, the hour sought.

2d. Suppose the moon to have been 18 days old, and the shadow cast by it on the sun-dial to have marked eleven. This time is subtracted from the hour when the moon was in the meridian on that day, and from which the hour marked by the shadow must be deducted. The shadow shows here 11 o’clock in the forenoon, or one hour before noon, which, deducted from 2h. 24m. gives 1h. 24m.; 2⅖ - 1 = 1⅖, or 24 minutes past one o’clock.

THE PHYSIOGNOTYPE.

This is a newly-invented instrument, by the aid of which a person may have a plaster cast of his face taken without submitting to the usual unpleasant process.

It consists of an assemblage of very fine moveable wires, confined closely together within a broad hoop or band, after the manner of the bristles in a telescope hearth-brush, but not closed at the back, in order to allow to the wires a free passage. The wires slide in a metal plate, perforated all over with holes, very fine and close together. The apparatus is surrounded by an outer case which is filled with warm water, in order to prevent any unpleasant sensation on the contact of the instrument with the skin.

When it is desired to take a likeness, the instrument is applied to the face with a gentle and gradual pressure, the wires easily yield and slide back, conformably to the prominences of the countenance; they are then fixed tightly in their position, and thus form a mould which will yield a perfect and faithful cast of the face, in which even the most minute line will appear with the strictest accuracy.

INFINITE DIVISIBILITY OF MATTER.

Dissolve a single grain of copper in about one dram of nitric acid, and dilute the solution with about one ounce of water, when it will be evident that a single drop of the mixture must contain an almost immeasurably small portion of copper. Yet, if the blade of a knife be dipped into it, it will become covered with a coat of copper; thus showing that the copper can be infinitely divided without any alteration in its properties.

HOLDING THE BREATH.

If a person inspire deeply, he will be able, immediately after, to hold breath for a time, varying with his health, state of exertion, or repose. A man, during an active walk, may not be able to cease breathing for more than half a minute; but, after resting on a chair or bed, he may refrain from breathing for a minute and a half, or even two minutes. But if he will prepare himself by breathing deeply, hardly, and quickly (as he would naturally do after running), and ceasing that operation with his lungs full of air, then hold his breath as long as he is able, he will find that the time, during which he can remain without breathing, will be double, or even more than double the former. This effect may be rendered exceedingly serviceable, as on many occasions a man who can hold breath for a minute, or two minutes, may save the life of another; such as in entering a chamber on fire, rescuing from drowning, &c.

SAND IN THE HOUR-GLASS.

It is a remarkable fact, that the flow of sand in the hour-glass is perfectly equable, whatever may be the quantity in the glass; that is, the sand runs no faster when the upper half of the glass is quite full than when it is nearly empty. It would, however, be natural enough to conclude that, when full of sand, it would be more swiftly urged through the aperture, than when the glass was only a quarter full, and near the close of the hour.

The fact of the even flow of sand may be proved by a very simple experiment. Provide some silver sand, dry it over or before the fire, and pass it through a tolerably fine sieve. Then take a tube, of any length or diameter, closed at one end, in which make a small hole, say the eighth of an inch; stop this with a peg, and fill up the tube with the sifted sand. Hold the tube steadily, or fix it to a wall, or frame, at any height from a table; remove the peg, and permit the sand to flow in any measure for any given time, and note the quantity. Then, let the tube be emptied, and only half or a quarter filled with sand, measure again, for a like time, and the same quantity of sand will flow: even if you press the sand in the tube with a ruler or stick, the flow of the sand through the hole will not be increased.

The above is explained by the fact, that when the sand is poured into the tube, it fills it with a succession of conical heaps, and that all the weight which the bottom of the tube sustains, is only that of the heap which _first_ falls upon it; as the succeeding heaps do not press downward, but only against the sides or walls of the tube.

RESISTANCE OF SAND.

From the above experiment it may be concluded, that it is extremely difficult to thrust sand out of a tube by means of a fitting plug or piston; and this, upon trial, is found to be the case. Fit a piston to a tube (exactly like a boy’s pop-gun), pour some sand in, and try with the utmost strength of the arm to push out the sand. It will be found impossible to do this: rather than the sand should be shot out, the tube will burst at the sides.

GLASS BROKEN BY SAND.

If bullets be let fall on glass which has been cooled in the open air, they will not break it; but, if a few grains of sand be let fall on the same kind of glass, it will be broken into a thousand pieces! This is explained by the lead not scratching the surface of the glass; whereas the sand, being sharp and angular, scratches sufficiently to break it.

TO BLEACH IVORY.

Place any piece of discoloured ivory beneath a glass, expose it to the sun, and it will soon be restored to pure whiteness; whereas, if the ivory be exposed to the sun without the glass covering, it will become more discoloured.

VANISHING SHELLS.

Put into a little diluted muriatic acid, a common whelk-shell, when it will be completely dissolved, and not a sensible trace of it left behind.

If an oyster-shell, or land snail-shell be put into the acid, their substances will disappear, but the form or skeleton of the shells will remain.

THE MAGIC EGG.

Fill a basin with dilute muriatic acid, and put into it an egg, which will sink; but, in a few seconds, the whole of the egg-shell being covered with bubbles of carbonic acid gas, will rise to the surface, a portion of the egg will be lifted above the surface, and the whole egg will slowly rotate. This rotation is formed by the bubbles of gas forming at the under part of the egg, and over all the submersed portions, which render them lighter than the portions above the liquid level, till the under portion ascends and the other descends.

THE MAGIC WHIRLPOOL.

Fill a glass tumbler with water, throw upon its surface a few fragments or thin shavings of camphor, and they will instantly begin to move and acquire a motion, both progressive and rotatory, which will continue for a considerable time. During these rotations, if the water be touched by any substance which is at all greasy, the floating particles will quickly dart back, and, as if by a stroke of magic, be instantly deprived of their motion and vivacity.

In like manner, if thin slices of cork be steeped in sulphuric ether in a closed bottle, for two or three days, and then placed upon the water, they will rotate for several minutes, like the camphor; until the slices of cork having discharged all their ether, and become soaked with water, they will keep at rest.

If the water be made hot, the motion of the camphor will be more rapid than in cold water, but it will cease in proportionately less time. Thus, provide two glasses, one containing water at 58 degrees, and the other at 210 degrees; place raspings of camphor upon each at the same time; the camphor in the first glass will rotate for about five hours, until all but a very minute portion has evaporated, while the rotation of the camphor in the hot water will last only nineteen minutes; about half the camphor will pass off, and the remaining pieces, instead of being dull, white, and opaque, will be vitreous and transparent, and evidently soaked with water. The gyrations, too, which at first will be very rapid, will gradually decline in velocity, until they become quite sluggish.

The stilling influence of oil upon waves has become proverbial: the extraordinary manner in which a small quantity of oil instantly spreads over a very large surface of troubled water, and the stealthy manner in which even a rough wind glides over it, must have excited the admiration of all who have witnessed it.

By the same principle, a drop of oil may be made to stop the motion of the camphor as follows: throw some camphor, both in slices and in small particles, upon the surface of water, and while they are rotating, dip a glass rod into oil of turpentine, and allow a single drop thereof to trickle down the inner side of the glass to the surface of the water; the camphor will instantly dart to the opposite point of the liquid surface, and cease to rotate. If a piece of hard tallow or lard be employed, the motion of the camphor will be more slowly stopped than by oil or fluid grease, as the latter spreads over the surface of the water with greater rapidity.

If a few drops of sulphuric or muriatic acid be let fall into the water, they will gradually stop the motion of the camphor; but, if camphor be dropped into nitric acid diluted with its own bulk of water, it will rotate rapidly for a few seconds and then stop.

If a piece of the rotating camphor be attentively examined with a lens, the currents of the water can be well distinguished, jetting out, chiefly from the corners of the camphor, and bearing it round with irregular force.

The currents, as given out by the camphor, may also be seen by means of the microscope; a drop or two of pure water being placed upon a slip of glass, with a particle of camphor floating upon it. By this means, the currents may be detected, and it will be seen that they cause the rotations.

Or, a flat watch-glass, called a _lunar_, may be employed, raised a few inches, and supported on a wire ring, kept steady by thrusting one end into an upright piece of wood, like a retort stand. Then put the camphor and water in the watch-glass, and place under the frame a sheet of white paper, so that it may receive the shadow of the glass, camphor, &c., to be cast by a steady light placed above, and somewhat on one side of the watch-glass. On observing the shadow, which may be considered a magnified representation of the object itself, the rotations and currents can be distinguished.[B]

[B] Abridged from the Magazine of Popular Science, vol. iii.

MAGIC PORCELAIN.

A peculiar kind of porcelain was formerly manufactured in China, which exhibited its colour and devices only when filled with water. Though the art of manufacturing this porcelain has been lost, and the mode cannot now be described with accuracy, the following has been conjectured as not very remote from the truth. The first requisite was that the vessel be extremely thin, so that the figures to be formed might be sufficiently clear and perceptible. After the vessel has been baked, the figures, which were mostly fish, (as those were most appropriate with the water), were formed on the inside; and, after the colour had dried, a second extremely thin coat, of the same substance as that of which the vessel was constructed, was lain on the inside and varnished. The fish, or other device, would then, it is evident, be enclosed between the two coats of the ware of which the vessel was made. All that remained to be done was to grind the outside of the vessel as close to the figures as possible, to varnish it again, and bake it a second time; and though, after this operation, the figures and embellishments would not be at all perceptible, yet, so soon as the vessel was filled with water, they would at once be rendered clear and distinct to a degree scarcely credible. Attempts have been made to revive this beautiful art, but hitherto without success.

A GALVANIC TONGUE.

Coat the point of the tongue with tin-foil, and its middle part with gold or silver leaf; when a sourish taste will be produced, and the tongue will be galvanised.

DRINKING PORTER OUT OF PEWTER.

If porter be drunk out of a pewter pot, it will produce a more brisk sensation than when it is taken out of a glass vessel, which is ascribed to a galvanic effect. In this instance there is a combination of one metal and two dissimilar fluids, which combination constitutes a galvanic circle. In the act of drinking, one side of the pewter pot is exposed to the action of the saliva, which moistens the lip, while the other metallic side is in contact with the porter; the circuit being thus completed, an agreeable relish is communicated to the beverage when it comes in contact with the tongue.

ELECTRIC OR GALVANIC PRESERVATION.

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.