Chemistry for Youth.
HEAT, LIGHT, AND FLAME.
A LANTERN TO GIVE LIGHT UNDER WATER.—The lantern must be made of leather, which will resist the waves better than any other substance, and must be furnished with two tubes, having a communication with the air above. One of these tubes is to admit fresh air for maintaining the combustion of the candle, and the other to serve as a chimney, by affording a passage to the smoke; both must rise above the surface of the water. The tube which serves to admit fresh air must communicate with the lantern at the bottom, and that which serves as a chimney must be connected with it at the top. Any number of holes may be made in the leather of which the lantern is constructed, into which glasses are fitted; by these means the light will be diffused on all sides. In the last place, the lantern must be suspended from a piece of cork, that it may rise and fall with the waves.
EXPERIMENT WITH A PIPE.—Compose a powder with one ounce of saltpetre, one ounce of cream of tartar, and one ounce of sulphur, pulverized singly, then mixed. Put a single grain of this powder into a tobacco-pipe, and when it takes fire it will produce a very loud report without breaking the pipe.
SINGULAR EFFECT OF HEAT.—If a piece of tin foil be wrapped in a piece of platinum foil of the same size, and exposed on charcoal to the action of the blowpipe, the union of the two metals is indicated by a rapid whistling, and by an intense brilliancy in the light which is emitted. If the globule thus melted is allowed to drop into a basin of water, it remains for some time redhot at the bottom: and such is the intensity of the heat, that it melts and carries off the glaze of the basin from the part on which it happens to fall.