How To Do Mechanical Tricks - free ebook by A. Anderson

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How To Do Mechanical Tricks

A. Anderson

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53 chapters

HOW TO DO MECHANICAL TRICKS.

HOW TO DO MECHANICAL TRICKS.

Containing complete instruction for performing over sixty ingenious Mechanical Tricks. By A. ANDERSON. FULLY ILLUSTRATED. New York : FRANK TOUSEY, Publisher, 24 Union Square . Entered according to Act of Congress, in the year 1902, by FRANK TOUSEY, in the Office of the Librarian of Congress at Washington, D. C. HOW TO DO MECHANICAL TRICKS....

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The Pile of Draughtsmen.

The Pile of Draughtsmen.

“Matter is inert.” That is what you read in every treatise on physics—what does it mean? Here is a very simple experiment that will prove this truth to anyone. Pile up ten draughtsmen, as shown in Fig. 1 . Before this pile place another piece on edge, and pressing its circumference with the forefinger, let it glide from underneath so that it strikes the pile with considerable force. The piece so thrown must, you will think, upset the whole pile of draughts; but no: the piece thus sharply sent fo

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The Decanter, Card, and Coin.

The Decanter, Card, and Coin.

This law of “Inertia” will provide us with a few more experiments as curious as they are conclusive. Place a playing or an ordinary visiting card on a decanter; upon the card and just in the center, over the aperture of the decanter, put a small coin (a dime). Now, if with a sharp fillip, given horizontally on the edge of the card, you succeed in whisking it off (which is very easy), the coin will fall to the bottom of the decanter. The following phenomenon has taken place: the movement was too

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A Clever Blow.

A Clever Blow.

Take a thin stick about a yard long, and thrust a pin firmly in each of its extremities. This done, place the stick on the bowls of two pipes, which a couple of persons hold by the stems, in such a manner that the pins only rest on the pipes. A third person then strikes the stick sharply in the middle, and it will break without injuring the pipes. Ordinary clay pipes will do very well, as the more brittle the pipes are, the more striking is the experiment. How is this explained? The mechanical e

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The Obedient Coin.

The Obedient Coin.

Take an ordinary wooden matchbox, and remove the drawer holding the matches. In the center place a small coin, a cent will be the best for the experiment, the object of which is to make the coin fall into the interior without touching it. Tap lightly on that side of the box to which you desire the coin to come, until it rests upon the edge. Then slightly raise the end of the box whereon the coin rests, and lightly tap with the finger once more. At once the coin will fall into the box. The secret

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To Cut a String With Your Hands.

To Cut a String With Your Hands.

With a little practice, and some briskness of movement, you may be able to break a string of considerable thickness by proceeding as follows: Wind the string round your left hand, so as to make a loop, as shown in the figure. Pass it three or four times round the fingers to insure the solidity of the loop. Seize firmly the other end of the string with your right hand, around which you wind it three or four times, then give a brisk pull. The string will be clean cut at the junction of the loop in

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The Rebound.

The Rebound.

On the neck of a bottle place a cork in an upright position. The cork must be large enough to rest on the neck without falling in. Now give a sharp fillip on the neck of the bottle, and you will see the cork fall, not on the other side of the bottle as most people expect, but forward in the direction of the hand giving the blow. This, again, is an illustration of the principle of inertia. A rapid blow tends to push the bottle from the cork before the movement is transmitted to the latter. Few pe

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A Fiery Catapult.

A Fiery Catapult.

Take a match-box and place it upright edge-wise and place two matches in each side between the inner and outer box, heads up. They must be inserted deeply enough to stick firmly. Place a third match cross-wise between them and it will stay there by the pressure the latter exercises on them. Now light the middle of the horizontal match and wait. What do you think will happen? Ask the bystanders which will first catch fire? The natural conclusion they will draw will be the following. From the midd

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To Make an Exact Balance.

To Make an Exact Balance.

To construct by yourselves, with the help of simple materials a balance of great precision may seem impossible. Nevertheless it can be done. A ruler, a tin box, (in which blacking was contained, for example) three blocks of wood, two pins, thread, four nails, a small piece of glass, and cardboard are all the necessary materials, and now to work. At a short distance from the center of the ruler, and on a cross line with one another, stick two pins so that they come out a little on the other side.

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The Recomposition of Light.

The Recomposition of Light.

It is a great pity that exquisitely beautiful facts and mysteries are wrapped up in the crack-jaw terms of foreign languages, and so made to appear ugly. There is no branch of knowledge more fascinating than light. To follow up its study is like walking along a shady lane, where at certain distances apart the wayfarer lights upon jewels of great brilliance. It has been said above that white light is formed by the union or combination of seven colors. When a ray of light passes through a prism it

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The Mysterious Apple.

The Mysterious Apple.

Pierce an apple in such a manner as to obtain two holes tending toward the middle, and forming a pretty large angle as shown in the figure. Two quills or tin tubes should be inserted to make the inside passages smooth. Pass a string through the hole and your apple is prepared for a little trick, which, you may be sure will astonish all persons before whom you practice it, and who of course are not yet initiated. You fasten one extremity of the string to your foot, and take the other in your hand

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Economical Letter-Scales.

Economical Letter-Scales.

Take a watch or small clock spring, and fix it by the center on a stick. At the other end attach a small brass hook to hold letters, etc., as shown in the figure. At the top of the hook fix horizontally a small band, running over a strip of cardboard, likewise hanging on the stick. Now graduate the cardboard strip with real weights, or their exact equivalents, and after this any small articles may be weighed with sufficient accuracy. The spring, being of steel, always turns to its original posit

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Tracing a Spiral.

Tracing a Spiral.

In geometry the process for tracing a spiral by the help of compasses is pretty long and tedious. The following method will enable you to do it far more quickly and as accurately. Take a wooden or cardboard cylinder, with a diameter equal to a fourth part of the distance you require between the spires (or trelices) to be traced. On this cylinder fasten one end of a string, B, and wind it up, and attach to the other end a pencil, C, or a point, according to what you want to do. Now you have only

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The Inclined Plane.

The Inclined Plane.

Take a piece of paper, roll it up into a tube large enough to hold a marble, and gum it lengthwise. Then introduce a marble and close the extremities with a strip of paper as shown below. When you think that it is well dried you place it upright on the upper end of an inclined board, or flat ruler, leaning on a pile of books for example. You will then see the paper cylinder lie down, get up and so on till it reaches the bottom of its course. The effect is very curious and will be more so if you

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To Cut a Bottle With a String.

To Cut a Bottle With a String.

Gum first two circular pads of paper on each side of the spot where you intend to cut your bottle. These pads are obtained by gumming several strips of paper one over the other, so as to leave between them a groove on which you wind the string round once. Catch hold of the extremities of the string, and draw it to and fro, see-saw fashion, by which friction the part of the glass operated on will be heated. As soon as you think that the glass is hot enough, plunge the bottle in cold water, which

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Equilibrium of a Knife in Mid-Air.

Equilibrium of a Knife in Mid-Air.

Be reassured dear readers, we are not going to ask you to make a balance in mid air, that would be too much for our weak capabilities. The question is simply to swing a knife horizontally in the space which surrounds us. The experiment is curious and easily executed. Take the cork of a champagne bottle. Pierce it lengthwise with a sharp knife, and let the knife stick out a third of its length from the thin end of the cork. Then insert into each side of the cork the prongs of two forks, so that t

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A Trick With Four Matches.

A Trick With Four Matches.

Speaking of matches, there is yet one more trick to be played with four of them. At the non-phosphoric ends of two matches cut a small notch so that they fit into each other. Stretch the matches apart so as to form an angle, and place them vertically upon the table. Then lean a third match against them so as to form a tripod, standing by itself. The question now is to take up this trivet with a fourth match and carry it to another place without disturbing the harmony of the little construction.

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The Distance of an Inaccessible Point.

The Distance of an Inaccessible Point.

Everyone knows what an angle is, and you say at once it is the inclination of two lines that meet each other. These lines by their branching off form an opening more or less wide. This opening is measured by the aid of an instrument called a protractor made of brass or horn, which finds its place in nearly every box of mathematical instruments. It represents a semi-circumference, divided into 180 equal parts, called degrees, written thus: 180°. Each degree is divided into 60 minutes, expressed t

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Practical Tracing of a Meridian Line.

Practical Tracing of a Meridian Line.

The meridian line of a place is an imaginary line passing through this place and the center of the sun, when the latter is at the highest point of the arc of the circle, which it daily describes. At that very moment it is noonday exactly at the place in question. As the position of the earth changes from day to day, the sun does not every day touch the meridian line at noon; sometimes it is in advance, sometimes behind. Various instruments have been invented to indicate in a practical manner the

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To Measure the Height of a Mountain.

To Measure the Height of a Mountain.

One can, without instruments, take the height of a building or a mountain, provided you are able to measure their base. A yardstick and two ordinary sticks are enough. Suppose the height of the tower, E F, is to be taken. Some distance off plant a stick, a yard high, A B; one yard from this we plant another and longer one, C D. Measure exactly the distance, B F, and applying the eye at A, we aim at the summit of the tower, E; mark on the stick, C D, the point where the visual ray meets the stick

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To Take Up Four Knives with One.

To Take Up Four Knives with One.

Here is one more trick of equilibrium, which appears to be interesting enough to find a place among these experiments. We need not give any long explanations, for our figure fully illustrates the way in which it has to be executed. First place a knife straight before you, then two others which you place, blade upon blade, over the first. Finally, the two last ones are arranged transversely, their blades passing over those of the two knives put down in the second instance, and below the blade of

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The Tack in the Ceiling.

The Tack in the Ceiling.

To nail a tack in the ceiling without hammer, using a ladder or chair to reach it, seems as impossible as pulling the moon down from the sky. Yet, with a little cleverness, it is quite an easy thing to do. Place a tack, head downwards, on a half dollar, then place a small piece of tissue paper over it, so that the point of the tack passes through. Then turn the sides of the paper down round the coin. Throw the whole, point upwards, violently against the ceiling, trying to keep this projectile of

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The Jumping Pea.

The Jumping Pea.

Take an unbroken straw, four or five inches long, not closed by knots, but forming a tube, and about one twentieth of an inch in diameter. Divide one of its extremities to a length of about half an inch in four, five or six parts, which separate slightly, so as to form a truncated cone. After having thus prepared the straw, take a dry pea, with a larger diameter than that of the tube, and place it in the cone. Hold the tube upwards, and blow into it at the opposite end. The pea will be forced up

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To Acquire a True Eye.

To Acquire a True Eye.

Here is a peculiar and clever recreation, easily performed, though at first sight it may appear difficult. Put a tumbler upside down. By means of bread crumbs, fix a match vertically on the top. On the edge of the table place another match, partly raised on a piece of cork or wood. Stoop down and aim at the vertical match on the glass, so that the one on the table is in the exact line of fire. When you think it is aimed straight, give it a fillip on the lower end, it will shoot up and touch the

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The Air-Tight Stopper.

The Air-Tight Stopper.

How many times has it happened to you, when wanting to cork a bottle, that the intended cork was too large to enter the neck? What have you done? Cut the cork all round, and obtained, but imperfectly, the desired end. Next time when the same occasion arises, turn the difficulty in this way: Instead of attacking the sides, cut four notches, bevel-shaped, into the cork as shown in the figure. Treated in this manner your cork will fit, and close the bottle hermetically....

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The Fusee Rocket.

The Fusee Rocket.

For this you only want a simple match box. Take out a match, and holding it on to the box as shown in figure, i.e. , hold the box a little slanting, between the thumb and forefinger, and place the match head downwards on the side of the emery paper, where the match ignites when rubbed against. With medium force press on the match and with the other hand give it a fillip in the direction indicated by the arrow. The little missile will fly into the air all ablaze, and fall down at a distance of fo

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A Novel Table Mat.

A Novel Table Mat.

To construct this original table mat 6 objects, always at hand when table is laid for a meal, are required; 3 knives and three tumblers of equal size and arrange the tumblers upside down, in the form of a triangle, and on each of them rest the handle of a knife. Cross the blades so that the first laid passes over the second and the second over the third, this latter passing over the first X. The blades sustain themselves and you may place on them a dish or any other heavy object, without being a

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Geometrical Paper Band.

Geometrical Paper Band.

Take a band of paper, say a postal wrapper; you observe that it has two lines and two surfaces (interior surface and exterior surface.) The problem is to arrange it so that it presents only one line and one surface. It may seem improbable, yet it is possible as you will see. Cut the band and gum together again the two pieces thus separated, after having turned over one of them as shown in figure as above. Arranged in this manner the paper has but one line and one surface, for it has the aspect o

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Photographic Camera.

Photographic Camera.

Here is a simple way to construct a camera for a pocket photographic apparatus. Fig. 1. Cut out of strong cardboard a piece of about 2 to 2 1 / 4 inches square. In the middle cut out a circle a little smaller than the lens with which you cover it, so that this lens holds on the edge of the hole. Cut out also two triangles of cardboard, having one side equal to the square, and a length in proportion to the focus of the lens; say for a simple lens of 3 inch focus, and one inch diameter, a length o

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The Phantom Needle.

The Phantom Needle.

You know that when you sit at a window with a looking-glass in your hand, you can catch a beam of sunlight on the glass and throw it into the eyes of a person on the other side of the street. What have you done in this case? You answer at once that you have bent the sunlight out of its course and turned it in another direction. If the glass were not there it would fall in a straight line on the window seat. This bending out of the straight line is called reflection. Now for an experiment; cut a

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Amphitrite.

Amphitrite.

At fairs, and in halls of mysteries a variety of optical illusions are presented. Under the name of Amphitrite, the spectacle is sometimes of a woman who seems to rise from the deep, moves about in the empty space, apparently without being sustained by anything or anybody. She seems completely isolated in mid-air. She turns about, sometimes in a circle, moving now the legs, then the arms. Then after several graceful evolutions in all directions, she stands straight and descends rapidly, seemingl

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Optical Illusions.

Optical Illusions.

Illusions of the eye are numberless, and afford a wide field for experiment. For example, if you ask any one wearing a silk high hat, to what height he thinks his hat would reach if placed on the ground against the wall or door. Nine times out of ten the mark of the height guessed will be half as much again, at least a third over the real height of the hat. Again, represents two triangles. Ask which is the one whose center is the better indicated. Every one will say, “triangle A.” Well, every on

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The Insensible Coin.

The Insensible Coin.

Cut a piece of cardboard about six inches long, and by sticking the extremities together with a pin, or with gum, form a circle or ring. Balance it carefully on the neck of a wine bottle or decanter, and on the top of the ring place a dime, exactly over the neck of the bottle. Now the trick to be performed is to take off the ring so that, without touching it, the coin falls into the bottle. On the inner side of the ring give a sharp knock with the finger, or, better still, with the thumb and for

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The Asses’ Bridge.

The Asses’ Bridge.

Every schoolboy knows which is the famous geometrical theorem, commonly called the Asses’ Bridge, and which is propounded as follows: The square constructed on the hypotenuse of a right angled triangle is equivalent to the sum of the squares constructed on the two other sides. If we had only to propound this terrible theorem, it would be an easy matter, but the question is to prove it by A and B, and by means of the triangles, similar angles, equivalents, etc. Well, instead of all this, we give

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Another Way to Prove the Preceding Theorem.

Another Way to Prove the Preceding Theorem.

In a square A B D C, trace four similar and equal triangles; cut them out and dispose them as shown in Fig. 1 . You will have in the middle an empty space forming a great square, which just has one of the sides of the hypotenuse of the right-angled triangle A E B. Trace the outlines of this square and remount the triangles one against the other, H C E, against A E B, and C D G, against B F G, you will get the Fig. below. Fig. 1. The successively covered and uncovered parts of the two squares hav

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Indented Angles.

Indented Angles.

Given two sheets of paper of the same size and form of a rectangle, fold them both in four equal parts, one lengthwise and the other sideways, as shown below. Fig. 1. When so folded take a fourth part off each. Part A in the figures. The question is now to cover quite exactly one of the remaining surfaces with the other, in cutting the latter in two perfectly equal parts. Fig. 2. To resolve this question take the surface (parts A having been detached), with which it is intended to cover the othe

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A Cheap Shooting Gallery.

A Cheap Shooting Gallery.

With a whalebone stay busk, make a bow and draw a target on a card. For the arrows, divide lengthwise a steel nib, choosing long shaped ones in the form of a lance and fix each part at the end of a match. You now have complete a saloon shooting gallery, inoffensive and sufficiently recreative at least for your smaller friends....

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The Coin in Equilibrium.

The Coin in Equilibrium.

Here is a curious demonstration of the balancing of bodies having their center of gravity displaced by a counterpoise. We propose to keep a coin horizontally in equilibrium on the rim of a tumbler, and it must rest on the glass only by its extreme edge, as shown by the figure which gives the complete demonstration. Take a silver dollar and place it between the prongs of two forks covering each other, then place the edge of the coin upon the glass and draw the handles of the forks together, or di

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The Submerged Coin.

The Submerged Coin.

In order to make the previous experiment more significant, you may present it also in the following manner: In a soup plate place a coin; beside the latter an inverted glass, then pour water into the plate just to cover the coin. You then inform the spectators that you will withdraw the coin from the plate without wetting your fingers. You will meet with a great deal of disbelief from many of your friends looking on. Leave them in doubt as to the success of your operation. Cut a round piece off

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The Smoke Rings.

The Smoke Rings.

When the air of a room is very calm, have you ever noticed that tobacco smoke rises slowly and in a nearly vertical direction? Have you never watched with interest the grayish or bluish streaks of smoke issuing from the smoke of a cigar or pipe? And in seeing the smoke rise in such a capricious fashion, have you ever ascertained that it is due to the calm of the surrounding air? One may get some amusement out of the agitation of the atmosphere. For the materials you only require a square or roun

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The Walking Cork.

The Walking Cork.

Stick two knives in a cork, on the same level, and opposite each other, so as to form a balance. In the bottom of the cork, at an equal distance, insert two pins, sufficiently deep not to bend under the weight which they will have to carry. Rest the pins on a flat ruler, slightly inclined, and give them a slight balancing movement. The weight of the apparatus will fall on the pin, A, on which the whole turns the knife placed at the side, B, will knock against the support, and will tend to bring

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The Obstinate Cork.

The Obstinate Cork.

Take a glass or metal tube, closed at one end, and cut a stopper in cork or india-rubber to its size so that it closes the tube hermetically, and take care that it glides in the tube without difficulty, and pierce it with a hole. On the top of this hole adapt a small piece of leather, rather larger than the hole, which you must take care to wet before proceeding with the following experiment. In order to be able to withdraw the cork when in the tube, you take the precaution to fasten in it both

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Petroleum Pulverizer.

Petroleum Pulverizer.

With the aid of the compressed air reservoir you are able to conduct various soldering operations, requiring often great heat. Let us construct the following pulverizer: Into a bottle of the shape shown in the figure, put some petroleum, and introduce a glass tube that does not quite reach the bottom. Close with wax that no air can enter, and at the upper extremity of the tube let a fitting be embedded, a section of which is shown in the engraving. This fitting has three openings, two horizontal

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Electric Attraction and Repulsion.

Electric Attraction and Repulsion.

The poles of the same sign repel, and the contrary poles attract each other, or, in other words, the negative, or the positive electricity attracts the electricity of a contrary sign, whereas the electricities of the same signs repel each other. In order to demonstrate this principle we will contrive a little plaything which will be as interesting as amusing to see in operation. For a pivot take a needle stuck in a cork, and, as magnetic needles, two old corset steels will do very well. If these

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The Bust of the Sage.

The Bust of the Sage.

Every person wonders how the sensational decapitation scene is produced. To all appearance a head is thrust through the neck opening of a guillotine, the knife descends and the head is cut off. However, in order that none of the fair sex may be alarmed, it may be varied as follows: In a cabinet a mirror is set across, sloping from the top at the back to the front. It reflects the ceiling, which is covered with the same material as that which is seen of the floor in front of the mirror. In the ce

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The Witchery of the Hand.

The Witchery of the Hand.

In order to ascertain the existence of animal magnetism the following apparatus, very simple, and not at all difficult to construct, answers perfectly. Stick a pin in a cork, point upwards. On that pivot place horizontally a sheet of paper so that it remains in perfect equilibrium. If you now put your hand over the sheet of paper, a rotary movement will manifest itself, the sheet swerving from right to left. This movement is caused by the influence of the hand’s magnetism....

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The Perspectograph.

The Perspectograph.

This simple instrument, invented by Mr. Jarlot, renders the tracing of a sketch extremely easy, besides avoiding absolutely faults of perspective, which is, without doubt, the principal advantage of this instrument. Thanks to it, one obtains an easy reproduction on one plane of objects placed on different planes. Here is a description of this very simple instrument. A wooden frame A B C D, with a slot in the side, A B, in which a pane of glass can slide so as to cover the whole space of the fram

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Camphor in Water.

Camphor in Water.

If you put very small pieces of camphor on the water, you will see them turn round each other with great velocity. These movements are due to the diminution of the superficial tension of the liquid in the vicinity of the pieces of camphor. In order to stop them throw a drop of oil in the water, and you will produce a perfect calm. One may utilize the camphor for an amusing recreation. Construct a small paper or cardboard boat and fasten underneath on the hind part or stern a piece of camphor. Yo

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A Simple Multiplier.

A Simple Multiplier.

Write on a card or strong paper the letters, figures, etc., which you want to reproduce. Then all along the lines or tracing, with a needle, prick holes in close proximity at equal distances. Place the sheet so prepared on a pad made of several sheets of blotting paper, smeared with blue analine ink, or a mixture of lamp-black and oil. Fix the corners with tacks or drawing pins, and draw your copies by simply placing the blank sheets over the pricked one, and press them down. The words, figures

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The Drawing Room Mirror.

The Drawing Room Mirror.

On one of the faces of a pane of glass smear some lamp-black mixed with oil. If you place this glass, thus prepared, vertically on an engraving representing flowers, fruits, birds, etc., you will obtain an infinity of forms, some of which will be very striking. If you want to reproduce these, to fix their outlines, you have only to interpose a transparent paper, to draw along the glass pane a line in pencil and to trace over the part of the picture which terminates at the foot of the pane. Fold

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Elementary Gas-Burner.

Elementary Gas-Burner.

Fill an old round tin box, at least two inches high, with sawdust and pieces of blotting paper. Close it as well as possible, and introduce a small metal, or glass, tube in the lid to a depth of about one-third of the box. Make the joint tight with putty. Put this box on any two supports and place the flame of a lamp or candle underneath it. Soon the overheated sawdust and blotting paper will evolve vapors of alcohol and combustible gases. Approach a lighted match to the upper end of the tube an

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Rapid Vegetation.

Rapid Vegetation.

A cheap sponge can be converted into a hanging bunch of greenery for room decoration. Plunge it into hot water, press it dry, then put in its holes or pores seeds of millet, red clover, barley, linseed, grasses, etc., in fact any species of plants which germinate easily and produce, as far as possible, leaves or blades of different shades. Place the sponge thus prepared on a vase or in a saucer, or better still, suspend it in the recess of a window, where it may get as much sunshine as possible.

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Miniature Volcanoes.

Miniature Volcanoes.

In a rather large porcelain or glazed earthenware basin place a small quantity of nitrate of lead. This may be obtained for a few cents from any painters’ supplies store. Then upon it throw some flakes of sal ammoniac. Immediately a number of conical elevations will be formed, which give off vapors and burst with a popping noise. Altogether the experiment represents very exactly, volcanoes in a state of eruption. When the eruption ceases, the rough, broken state of the remaining mats, represents

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