INCOMBUSTIBLE LINEN.
Make a strong solution of borax in water, and steep in it linen, muslin, or any article of clothing; when dry, they cannot easily be inflamed.
THE BURNING CIRCLE.
Light a stick, and whirl it round with a rapid motion, when its burning end will produce a complete circle of light, although that end can only be in one part of the circle at the same instant. This is caused by the duration of the impression of light upon the retina. Another example is, that during the twinkling of the eye we never lose sight of the object we are viewing.
WATER OF DIFFERENT TEMPERATURES IN THE SAME VESSEL.
Of heat and cold, as of wit and madness, it may be said that “thin partitions do their bounds divide.” Thus, paint one-half of the surface of a tin-pot with a mixture of lamp-black and size, and leave the other half, or side, bright; fill the vessel with boiling water, and by dipping a thermometer, or even the finger, into it shortly after, it will be found to cool much more rapidly upon the blackened than upon the bright side of the pot.
WARMTH OF DIFFERENT COLOURS.
Place upon the surface of snow, as upon the window-sill, in bright daylight or sunshine, pieces of cloth of the same size and quality, but of different colours, black, blue, green, yellow, and white: the black cloth will soon melt the snow beneath it, and sink downwards; next the blue, and then the green; the yellow but slightly; but the snow beneath the white cloth will be as firm as at first.