Chapter LXIII: Mechanical and Other Puzzles

I.--SOME MECHANICAL PUZZLES.--BY F. CHASEMORE.

(1) _The Balance Puzzle._--Cut a piece of cardboard four inches square. In the middle punch two holes, and punch a hole also in each corner. Take four pieces of thread eight inches long and knot the ends together; then pass one thread through each corner hole of the card and fasten them there by tying a bead to each. Now take another piece of thread eighteen inches long and double it in the middle, then pass the loop down through one of the holes in the middle of the card and up through the other hole, and pass the loop through a small ring. Next pass the ends of the thread through the loop and draw it tight, and fasten the ends to the knot joining the four other threads (Fig. 1). The puzzle is to get the ring off the threads without cutting them.

Take the loop and pass it down through one of the corner holes under the thread, and pull the bead down through the loop. Do this to each corner, and the loop will now be seen to surround the whole of the threads: pass the loop down over the cardboard, when the ring will come off. To replace the ring reverse the movement.

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(2) _The Card Bridge._--Take a visiting-card and bend it as in Fig. 2, so that the parts bent up are half an inch high. Now place this card on a table, resting on the two bent parts. The puzzle is to blow the card bridge right over on to its back. This will not be so easy a job as it appears. The secret is in blowing on the table about six inches in front of the bridge.

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(3) _The Triangle Puzzle._--Take six pieces of stick about three inches long, and with them form four equilateral triangles, each triangle to have one stick for the side. This is done by placing three sticks in a triangle on the table, and placing a stick at each corner and letting these three sticks come together at the other ends.

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(4) _The Six Squares Puzzle._--Take seventeen pieces of stick three inches long and arrange them as in Fig. 3. The puzzle is, by taking away five sticks, to leave three perfect squares, and three only, these three squares to be three of those originally formed, and all the same size. To do this take the two sticks from the two top corners and the middle stick at the bottom.

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(5) _The Puzzle Box._--Take six visiting-cards and bend them as in Fig. 4. The puzzle is to put them together in the form of a box, making them fasten each other. The box will bear rough usage. This is done by fitting the cards together as in Fig. 4, when they will be found to fasten each other.

If you make a small hole in one of the sides and get one of your smoking friends to fill the box with smoke, on tapping gently the side opposite to the hole a beautifully perfect ring of smoke will issue from the hole, and you can produce any number you like.

II.--THOUGHT-GUESSING.

This game is not the same played by Irving Bishop a few years ago when he pretended to read the number of a bank-note held by a gentleman, but is quite as easy. This game was shown me by a friend home from Penang, where it is played a great deal, although not of foreign origin. It is played as follows:--One of the company goes out of the room while those remaining decide on something to be thought of; it may be something in the room or some idea suggested by something in the room. When this is decided upon, the absentee is admitted, and he has to guess what was thought of by asking questions, to which he only receives answer ‘Yes’ or ‘No.’ He may ask any question that will help him. The first question should be, ‘Is it a substance?’ ‘No.’ ‘Is it an abstract idea?’ ‘Yes.’ ‘Is the thing that suggested the idea in the room?’ ‘Yes.’ He should first localise the thing suggesting the idea by dividing the room by imaginary lines in all directions, and asking first if it is on one side, and then if it is on the other, always framing the question in such a manner that it can be answered by ‘Yes’ or ‘No’ as otherwise no answer will be given. The game allows of great ingenuity in selecting the idea and also in working up to it in finding it out. One of the ideas I had to guess once was this--the quantity of silex or flint in the cane of a chair on which I was sitting. And another was this--the curve formed by the head of the hammer when giving the last stroke to a particular nail in the wall. These look difficult, but if properly managed will be found to be guessable. The game improves by practice, as after two or three times you will be able to find out ideas that would at first have appeared impossible.

III.--AN IMPROVED RING PUZZLE.--BY HERR MEYER.

Among the many wire puzzles which I have seen at different times, I was pleased with one which had two loops. I therefore added a third and subsequently a fourth, and was successful in making the puzzle more interesting. Any boy can easily construct the toy of iron-wire with a pair of pliers from the accompanying illustration.

The large ring is 3 inches in diameter, and the bar is 4 inches long. The object is to remove the large ring by pushing it through the smaller ones. The movements are explained by means of the figures and letters written in the diagram. The ring of the bar is called B, the ring of the first loop is 1, that of the second loop is 2, and so on.

The large ring is folded by moving D upwards, so that it falls on C. Then A is pushed from the left to the right through 1, moved over B (that is, B is pushed through between the two wires), and drawn back through 1. Then the ring is folded the other way and pushed through 2 and 1, over B, back through 1, over 1 and B, and back through 2. Then all through 3. Then through 1, over B, back through 1; folded the other way; all through 2; then through 1, over B, and back; and the ring is off.

The ring is put on thus: Fold it, push it half length through 1, over B, back through 1; fold; all through 2; through 1, over B, back; fold all through 3; through 2, over B and 1, through 1, over B, back through 1 and 2, through 1, over B, back, and it is on.

When there is a fourth loop, then the ring is removed thus: Push it through 1, over B, back, fold, through 2 and 1, over B, back over 1 and B, back through 2, through 3 and 2, over B and 1, through 1, over B, back through 1 and 2, through 1, over B, back, over 2 and 1 and B, back through 3, all through 4, through 2, over B and 1, through 1, over B, back through 1 and 2, through 1, over B, back, fold, all through 3, through 1, over B, back, fold, all through 2, through 1, over B, back, off.

The ring is placed on the fourth loop thus: Fold it, push it half-way through 1, over B, back, fold, all through 2, through 1, over B, back, fold, all through 3, through 2, over B and 1, through 1, over B, back through 1 and 2, through 1, over B, back, fold, all through 4, through 3, over B and 1, through 1, over B, back, over 2, through 2 and 1, over B, back, over 1 and B, back through 2 and 3, through 2, over B and 1, through 1, over B, back through 1 and 2, through 1, over B, back, open the ring.

IV.--AËRIAL RINGS.

A few very pretty experiments can be made with smoke rings, and as the apparatus is cheap and easily procurable it may be worth while to say a few words about them. The best arrangement for producing satisfactory results is that shown in Fig. 1, where a glass jar with a tap at the base is resting on a stand. Into the jar and through the cork a small tube is fixed and the whole sealed down, so that all air passing into the jar must come through the tube. The finer the tube the better; the material is of no consequence--it may be of metal, glass, or clay--so long as the passage down it is kept clear. To it, as shown in the cut, a holder is fixed, to which the candle or what not is attached, so that the centre of the tube points fairly into the smoke. The jar is filled with water, the cork fixed down tightly, and the candle lighted. The tap is then turned, and as the water runs out it sucks down the smoke, and the rings will be seen rising through the water and forming on its surface, as shown in Fig. 2. These rings will soon disappear and gradually merge into a sort of collar, shown in Fig. 3, where the central bar is the tube leading up to the source of smoke.

There are other ways of producing smoke rings. For instance, rings such as shown in Fig. 4 are produced during the combustion of phosphuretted hydrogen, the white vapours of the phosphoric acid rolling up into the air in apparently whirling crowns. From guns and field-pieces the smoke often emerges in rings, and steam out of a small vertical jet is often shot forth in small circles, such as shown in Fig. 5.

There is, however, a far simpler way of making smoke rings than any we have described, and that is by procuring a cubical cardboard box with a small round opening in two of its opposite faces, filling it with smoke from burning brown paper, and sending the ring into the air by hitting the palm of the hand against one hole so as to eject the smoke wreath at the other. In this way most excellent rings are formed, and if received on a piece of damp glass the rings can be caught and held for a few moments for examination. In a quiet room free from draughts the regularity and duration of the rings will provide a surprise for those who have not tried the experiment.

V.--BUBBLE BLOWING.

We are all of us familiar with the ordinary bubble, and we have probably all had a try with a long clay pipe and a basin of suds, and succeeded more or less, principally less, in setting 4-inch balloons afloat over some quiet neighbourhood. It is possible that a few of us have filled such soap balloons with hydrogen, and by applying a light to them have caused an explosion in mid air. But how many of us have tried to attach a car to our bubbles?

This can be done easily after a little practice, and the sketches herewith make clear how to set about it. Get an ounce of glass tube from the nearest druggist, and cut out of thin paper whatever your fancy leads you to fix to the balloon. As something out of the ordinary lines, we give the exact size of an aëronaut we recently despatched on a cruise (Fig. 1). D is a small disc of paper--proper size; F is a fine thread--proper length below it is the paper figure, cut out of the orange wrapper of one of the _Boy’s Own Paper_ monthly parts, and it is traced from the figure we used.

To make the experiment a success it is as well to remember the conditions. The bubble rises because the air it contains is lighter than that which surrounds it; it floats when the air is of the same temperature, it falls when the air within is colder than the air without. The air in the bubble comes hot from the lungs, and the greater the difference in heat between that air and the air you breathe the higher will the bubble go. In short, to have bubbles in perfection you should blow them in an ice room! As it is not every one that can obtain the use of a meat storage safe for bubble blowing, let us make our first experiment in a cool room. Begin with working up a good stiff lather; and the better the soap the better the suds for our purposes. Use your tube as you would your pipe, and blow downwards into the basin steadily and strongly. Take a good breath of air to begin with, and hold it for a second or two. Keep the point of the tube downwards until you have fixed on the disc in the way shown in the sketch. No gum or stickiness is required: all you have to do is to let the dry disc drop lightly on the wall of the balloon; the moisture will keep it in its place provided the knot of the cotton is small enough. If you pass the cotton through with a needle and have the same sort of single knot as if sewing, the disc will answer all your requirements.

As soon as the disc is firmly fixed, turn the tube gently upwards, and away will go the bubble, aëronaut and all. It will not cross the Atlantic, but it will at least reach the ceiling; and if on a cold day you try it out of doors, you may get it to travel unchecked for several hundred yards.

VI.--MARIONETTES,

or _Fantoccini_, are very entertaining when dexterously worked, as they may be by a little practice. Say you have a table with drapery arranged round it to form a little platform, and drapery also at the back. Let the latter be dark in colour, so that the string, thread, or silk, with which you work the dolls, may be less distinguishable if they are so at all.

The human performer (out of sight) works the figures over the back drapery, moving every joint, and throwing balls about gaily, as in Fig. 1.

When _Living Marionettes_ are introduced--as they sometimes are at public exhibitions--the effects are most comical. On a small stage an ordinary man’s head is apparently attached to a miniature body, and this latter walks, dances, and goes through many antics. The head, too, has eyes ‘in a fine frenzy rolling,’ and is gifted vocally, being able to talk and sing as well as many persons who fill a much larger space in the world.

This is managed by having two backgrounds, one the height of the performer’s chin, the other--a little farther back--extending to the top of the scene. Both of these are black, and at a little distance the break in them is not distinguishable. The performers walk on a platform at a lower level than the stage, the doll-bodies being fastened beneath their chins, hanging over the front drapery, and the doll’s feet resting on the platform in view of the audience. The performers also carry black curtains attached to them (not perceptible against the similar background), and through these wires, fixed to the arms and legs of the manikins, are pulled to give them motion. (See Fig. 2.) We have also described ‘Living Marionettes’ in another part of this volume.

VII.--MODEL WRESTLERS.

A good deal of amusement can be had out of a pair of model wrestlers. The way in which the dolls are fitted and worked is sufficiently shown in the accompanying illustration. The legs are in one piece, and the arms are joined so that each doll has only four working parts. The feet are loaded to keep the figures upright on the string, but it is not necessary that this should be done, as they can be kept firmly on the table without. The device is a very old one. Curiously enough, in the _Hortus Deliciarum_ of Herrade de Lansberg, Abbess of Hohenburg--a manuscript over seven hundred years old, now in the Paris Library--a man and woman are represented playing with a couple of figures arranged very much on the same principle, the only difference being that the dolls are separate, and worked with two strings instead of one. The figures are knights in complete armour, with swords and shields. They are hung close together, so that the swords are crossed, and the heels are loaded to keep them upright. The strings are crossed, and held one in each hand by the man and woman. The cross comes between the figures, so that the string that is attached to the waist of one figure is fastened to the knee of the other, and any motion forward is balanced by one backward, and a most realistic encounter can be fought out almost automatically.

With the substitution of thin cap wire for the thread an excellent marionette or shadow show could be easily arranged, it being much easier to work horizontally than vertically in all cases where vigorous action is required to be simulated.