painful than agreeable; but if it be small, the electrification moderate, and none of the company touch the eyes, or the more tender parts of the face, the experiment is diverting enough to all parties.

Many of the preceding experiments may be also performed to advantage by a person standing upon the stool as above, and holding in his hand what was directed to be fastened to the prime conductor. If he hold a large plumy feather in his hand, it is very pleasing to observe how it becomes turgid, its fibres extending themselves in all directions from the rib; and how it shrinks like the sensitive plants, when any unelectrified body touches it; when the point of a needle is presented to it, or to the prime conductor with which he is connected.

If a dish, containing spirits of wine made warm, be brought to the electrified person, and he be directed to put his finger, or a rod of iron into it, the spirit will be immediately in a blaze; and if there be a wick or thread in the spirit, that communicates with a train of gunpowder, he may be made to blow up a magazine, or set a city on fire with a piece of cold iron; and at the same time know nothing of what he is about.

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An amusement of this sort may be performed by several persons, standing upon insulated stools, and many diverting circumstances may be added to those here mentioned. Care should be taken that the floor on which the stools stand be free from dust, but it is most eligible to have a large smooth board for that purpose.

The Inconceivable Shock.

Put into a person's hand a wire that is fixed on to the hook that comes from the chain which communicates with one side of the battery, and in his other hand put a wire with a hook at the end of it, which you direct him to fix on to the hook that comes from the other chain, which when he attempts, he will instantly receive a shock through his body, without being able to guess from whence it proceeds. The shock will be

in proportion to the number of jars that are charged; but it is remarkable, that a small shock gives a much more pungent sensation in passing through the body, than one that is large.

This amusement may be diversified, and rendered still more entertaining, by concealing the chain that communicates with that which comes from the outside of the battery, under a carpet, and placing the wire that communicates with the chain which comes from the inside, in such a manner that a person shall put his hand upon it without suspicion, at the same time that his feet are upon the other wire. Many other methods of giving a shock by surprise may be easily contrived; but great care should be taken, that these shocks be not too strong, and that they be not given to all persons indiscriminately..

When a single person receives a shock, the company is diverted at his sole expence; but all contribute their share to the entertainment, and all partake of it alike, when the whole company forms a circle, by joining their hands, and when the operator directs the person who is at one extremity of the circle to hold the chain which communicates with the coating, while he who is at the other extremity of the circle touches the other chain or wire. All the persons who form this circuit being struck at the same time, and with the same degree of force, it is often very pleasant to see them all start at the same moment, to hear them compare their sensations, and observe the very different accounts they give.

This experiment may be agreeably varied, if the operator, instead of making the company join hands, directs them to tread on each other's toes, or lay their hands on each other's heads. If, in the latter case, the whole company should be struck to the ground, as it once happened, when Dr. Franklin gave the shock to six very stout men, the inconvenience arising from it will be very little; the company that was struck immediately got up again, without knowing what had happened. This stroke was given with two jars, each of the measure of about six gallons, but not fully charged.

Magical Explosions.

We have shown in a preceding experiment how gunpowder may be fired by the intervention of spirits, but there is another method, more simple and expeditious, which we shall here describe. Make up gunpowder in the form of a small cartridge, in each end of which put a blunt wire, so that the ends within the cartridge may be about half an inch distant from each other, then joining the chain that comes from one side of the battery to one of the wires at the end of the cartridge, bring the chain that comes from the other side of the battery, to the wire at the other end, when the shock will instantly pass through the powder, and set it on fire.

By a similar method, fine brass or iron wire may be melted; for the explosion will pass from one chain to the other, though the wire, which will be first red hot, and then melt into round drops. A battery of 35 jars has entirely destroyed fine brass wire, of the 330th part of an inch in diameter, so that no particle of it could be found after the explosion. At the moment of the stroke, a great number of sparks, like those from a flint and steel, flew upward and laterally from the place where the wire was laid, and lost their light, in the day, at the distance of about two or three inches.

A stroke from a common jar will easily strike a hole through a thick cover of a book, or many folds of paper, leaving a remarkable bur or prominence on both sides, as if the fire had darted both ways from the

center.

The Prismatic Colour.

To the ends of each of the chains that come from the battery, fix an iron wire, and between those wires place a plate of tin, of about three inches square, and polished on one side, in a perpendicular direction.— The wire next the polished side should be finely pointed, and brought very near the surface of the plate.

By repeating the explosions of the battery, there will first appear a dusky red, about the edge of the central spot; presently after, generally after four or five strokes, there appears a circular space, visible only in an oblique position to the light, and looking like a shade on the plate: this expands very little during the whole course of the explosions. After a few more discharges, the second circular space is marked, by another shade beyond the first of one-eighth or onetenth of an inch in width, which never changes its appearance after any number of explosions. All the colours make their first appearance about the edge of the circular spot; more explosions make them expand toward the extremity of the space first marked out; while others succeed in their place, till after 30 or 40. explosions, three distinct rings appear, each consisting of all the colours in the prism or rainbow.

It makes no difference whether the electricity issue from the pointed wire upon the plate, or from the plate upon the pointed wire, the surface opposite the point being marked exactly the same in both cases. The points, themselves, from which the fire issues, or at which it enters, are coloured for about half an inch to a considerable degree, and the colours are repeated, as on the plate.

The innermost, that is, the last formed colours, on the plate, are always the most vivid, and those rings are also closer to each other than the rest. Those colours may be brushed with a feather or the finger without injury, but they are easily peeled off by the nail, or any thing that is sharp.

The Artificial Spider.

Cut a piece of burnt cork, about the size of a pea, into the form of the body of a spider; make its legs of linen thread, and put a grain or two of lead into it to give it more weight. Suspend it by a fine line of silk between the electrified arch and an excited stick of wax, and it will, like a clapper between two bells, jump continually from one body to the other, moving

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its legs, at the same time, as if animated; to the no small surprsie of those who are unacquainted with the electric influence.

The Artificial Earthquake.

In the middle of a large bason of water place a round wet board: this board represents the earth, and the water the sea. On the board erect an edifice, composed of several separate pieces, which may represent a church, a castle, a palace, or, if you please, all of them.

Then placing a wire that communicates with the two chains of the battery, so that it may pass over the board and the surface of the water, upon making the explosion, the water will become agitated, as in an earthquake, and the board moving up and down, will overturn the structures it supports; at the same time that the cause of this commotion is totally concealed.

The Electrical Kite..

Take a large thin silk handkerchief, and extend it, by fastening the four corners to two slight strips of cedar. The handkerchief thus prepared and accommodated with a tail, loop, and string, will rise in the air like a common paper kite. To the top of the upright stick of the cross is to be fixed a pretty sharp pointed wire, rising a foot or more above the wood. To the end of the twine next the hand is to be tied a silk ribband, and where the twine and silk join, a key or tin tube may be fastened.

This kite is to be raised when a thunder gust appears to be coming on, and as soon as the thunder clouds come over the kite, the pointed wire will draw the electricity from them, and the kite, with all the twine, will be electrified, the loose filaments of the twine will stand out every way, and be attracted by the finger. When the rain has wetted the kite and twine, so that it can conduct the electric fire freely, it will stream out plentifully from the key, on the approach of a man's