| 123456789 | ||
| 9 | ||
| ---------------- | ||
| 1111111101 |
Multiply by 18, instead of 9, and the product will consist of 2’s. By 27, and it will be 3’s. In this manner all the digits may be obtained by multiplying by the multiples of 9; as 36, 45, 54, etc.
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ONE WAY TO FIND THE NUMBER OF DAYS IN THE MONTH.
Count the knuckles of the hands, with the spaces between them; all the months with thirty-one days will fall on the knuckles, and those with less than thirty-one in the spaces. Thus, beginning with the forefinger of the left hand, July will come on the knuckle of the little finger; then beginning with August on the forefinger of the right hand, December will be reached at the knuckle of the third finger.
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SOME ELECTRICAL EXPERIMENTS.
Considerable amusement may be derived from the electrical phenomena manifested by a sheet of stout brown paper, when friction is applied to it. Having warmed such a sheet, and rubbed it with the dry palm of the hand, or some woolen fabric, giving six or eight smooth, steady strokes, with considerable pressure, and all in one direction, away from the body, then place a bunch of keys in the center of the paper, and lift it by the ends; a spark of electricity may now be taken from the keys.
If ordinary unglazed paper be immersed in a mixture of equal parts of sulphuric and nitric acids, then well washed with plenty of water and dried, it becomes extremely electric. If placed on a wooden table, or, better still, on a waxed cloth, and rubbed with the hand, it attracts feathers, pith-balls, fragments of paper, or other small light objects.
When suddenly stripped from the waxed cloth in a darkened room, the entire surface will have a luminous phosphorescent appearance. A spark can be taken from it by holding the finger about half an inch from the surface. If placed against the wall it will adhere to it and keep its place for several minutes.