5.—Take a piece of common brown paper, about the size of an octavo book, hold it before the fire till quite dry and hot, then draw it briskly under the arm several times, so as to rub it on both sides at once by the coat. The paper will be found so powerfully electrical, that if placed against a wainscoted or papered wall of a room, it will remain there for some minutes without falling.
6.—And if, while the paper adheres to the wall, a light fleecy feather be placed against it, it will be attracted to the paper, in the same way as the paper is attracted to the wall.
7.—If the paper be again warmed, and drawn under the arm as before, and hung up by a thread attached to one corner of it, it will hold up several feathers on each side; should these fall off from different sides at the same time, they will cling together very strongly; and if after a minute they be all shaken off, they will fly to one another in a very singular manner.
8.—Warm and excite the paper as before, lay it on a table, and place upon it a ball made of elder pith, about the size of a pea; the ball will immediately run across the paper, and if a needle be pointed towards it, it will again run to another part, and so on for a considerable time.
9.—Support a pane of glass, previously warmed, upon two books, one at each end, and place some bran underneath; then rub the upper side of the glass with a black silk handkerchief, or a piece of flannel, and the bran will dance up and down under it with much rapidity.
10.—Place your left hand upon the throat of a cat, and with the middle finger and the thumb, press slightly the bones of the animal's shoulders; then, if the right hand be gently passed along the back, perceptible shocks of electricity will be felt in the left hand. Shocks may also be obtained by touching the tips of the ears after rubbing the back. If the color of the cat be black, and the experiment be made in a dark room, the electric sparks may be very plainly seen. Very distinct charges of electricity may also be obtained by touching the tips of the ears after applying friction to the back, and the same may be obtained from the foot. Placing the cat on your knees, apply the right hand to the back; the left fore paw resting on the palm of your left hand, apply the thumb to the upper side of the paw, so as to extend the claws, and by this means, bring your fore finger into contact with one of the bones of the leg, where it joins the paw; when, from the knob or end of this bone, the finger slightly pressing on it, you may feel distinctly successive shocks, similar to those obtained from the ears. It is, perhaps, unnecessary to add, that, in order to this experiment being conveniently performed, the experimenter must be on good terms with the cat.
ELECTRICAL SHOCK FROM A SHEET OF PAPER.
Place an iron japanned tea tray on a dry, clean, beaker glass; then take a sheet of foolscap writing paper, and hold it close to the fire until all its hygrometric moisture is dissipated, but not so as to scorch it; in this state it is one of the finest electrics we have. Hold one end down on a table with the finger and thumb, and give it about a dozen strokes with a large piece of India rubber from the left to the right, beginning at the top. Now take it up by two of the corners and bring it over the tray, and it will fall down on it like a stone; if one finger be now brought under the tray, a sensible shock will be felt. Now lay a needle on the tray with its point projecting outwards, remove the paper, and a star sign of the negative electricity will be seen: return the paper, and the positive brush will appear. In fact, it forms a very extemporaneous electrophorus, which will give a spark an inch long, and strong enough to set fire to some combustible bodies, and to exhibit all the electric phenomena not requiring coated surfaces. If four beaker glasses are placed on the floor, and a book laid on them, a person may stand on them insulated; if he then holds the tray vertically, the paper will adhere strongly to it, and sparks may be drawn from any part of his body; or he may draw sparks from any other person, as the case may be; or he may set fire to some inflammable bodies, by touching them with a piece of ice.
LIGHT UNDER WATER.