Three Hundred Things a Bright Boy Can Do

by Unknown

A parachute may be dropped “from the clouds.” This may be simply a square of paper with a string at each corner and a figure hanging on at the ends (Fig. 11). The figure may be as rough as you like, detail would be lost. Or, two squares of paper may be used, the strings being crossed over the lower and kept in place by the upper, which should be pasted upon it (Fig. 15).

A more elaborate parachute may be made by folding a square of paper from corner to corner into a triangle. This should be folded again and once again from corner to corner when it will take the shape of Fig. 12. A cut through the dotted line and a couple of holes pierced at the dots will give, when opened out, Fig. 13; and a string passed through each hole and made to carry a car will give the complete parachute (Fig. 14).

A piece of cotton or twine should be passed through the parachute to attach it to the balloon. Then a piece of wire should be twisted and bent, as in Fig. 10, w. Fasten to this with thin wire a piece of time-fuse, t f, turned up as shown, and to the bend b attach the cotton. At the moment of ascension, light the top end of the fuse at a, and when it has burned to b the parachute will be liberated.

Fireworks may be lighted in the same way. You will need time-fuse, quickmatch, and such fireworks as you prefer. Blue lights, squibs, and fireworks of that description should be arranged as in Fig. 20. Here c is a cork or bung with holes bored in it for the insertion of the fireworks f f f f. Q is the quickmatch which is to light them simultaneously when the time-fuse, t f, has burnt far enough. A catherine wheel may be pinned at the bottom of the cork and connected with the quickmatch, or the pin may be dispensed with, when it will whizz through the darkness in grand style.

One of the most successful effects may be obtained with the balls or stars from Roman candles. You can, of course, pull the candles to pieces, but a better plan is to buy the balls at 6d. a dozen.

Bend a piece of wire into a circle (Fig. 16) and take two wires across at a right angle. Then place the balls, one by one, in pieces of tissue paper and cover them with meal powder and tie up the ends (Fig. 17), fastening them on the wire, as shown in Fig. 16. A piece of time-fuse, or quickmatch, q, as you want the stars to drop singly or in a shower, must next be passed through each ball packet and connected with lighted time-fuse. Of course the fireworks should hang some distance below the balloon. Crackers or maroons may be arranged as in Figs. 18 and 19, and many other devices invented.

Your balloon may also carry up a piece of magnesium wire with which the country may be lighted up, or it may take up a Chinese lantern—in fact there is no end to the fun which may be got out of it. You will find it difficult, however, to get an effect to beat the Roman candle balls.

Quickmatch costs 2d. or 3d. a six-feet length, according to the thickness required; time-fuse one penny an inch.

Bubble Balloons.—One reason for the short life of the bubble as usually blown is the excessive evaporation which takes place from the large surface presented to the air. As this evaporation of the fluid goes on, the film gets thinner, the tension gets more acute, accompanied by ever changing and brightening hues of colour, until the thin walls can no longer bear the strain, and the bubble bursts into fine spray. Another, perhaps, more powerful reason is the unequal strength of the walls, due to the drainage of the moisture from the upper parts of the bubble into the lower parts by its own weight. This produces a weak and thin area, denoted by the refraction of the blue rays of light in the top of the bubble, and it cannot resist the pressure from within. There are two ways of prolonging the life of a bubble. When the breath is first driven into the liquid, the force used is sufficient to send the fluid surging in all directions, and the film is fairly well nourished. Presently as the soapy water dipped out by the bowl of the pipe gets distributed over the walls of the bubble and it increases in size, this no longer acts, and drainage from the top at once sets in. If the blowing is now continued, the end so much the more quickly approaches. To enable you to continue enlarging the bubble and lengthen its life, feed it. This may be done readily and safely, by dipping a camel-hair brush in the soapy emulsion and, letting it touch the bubble at the top, when the fluid will stream down over the surface, thickening the film, and permitting you to get a bubble as big as your hat.

This is only a temporary expedient, a flank movement, and merely defers the end by a minute or two. To attack the difficulty with more success, change the mixture. Shred some Castile soap, which may be purchased by the pennyworth at the chemist’s, and beat up in the usual way with water; you will find that much more can be done with this preparation than the usual household soap. If your aim is merely to produce an overgrown, sagging, wobbling bubble, feed with a brush as above. For further experiments do not blow large unmanageable ones, but an ordinary sized bubble blown in this liquid will enable you to show its toughness, length of life, and other qualities. If your coat is made of a woollen fabric, release some bubbles on the shoulder; they will roll down the sleeve and tumble off to the floor, if they do not meet with any cotton fabric on the way; This is due to the repulsion which exists between wool and the watery film, doubtless due to the presence of fat in some form upon the fibres. While upon the sleeve they may be carried about the room, or passed from one person to another. This repulsion may be further utilized, too, and the bubble treated as a shuttlecock.