The appearances after cleath vary extremely. The body- sometimes retains the posi tion whi,.)11 it occupied when struck, while in other CaSCS it may be dashed to a consid erable distance. The clothes are often burned or torn, and have a peculiar singed smell; and metallic substances about the person present signs of fusion, while such as are composed of steel become magnetic. There ILIT generally marks of contusion or laceration, or, if they- are absent, extreme ecchymosis (q.v.) at the spot where the current -entered or emerged. In addition to wounds and burns, fractures have also been noticed.
The treatment must be directed to the special symptoms, which are liable to great variations. Sir B. Brodie's advice is as follows: "Expose the body to a moderate -warmth, so as to prevent the loss of animal heat to which it is alway-s liable when the functions of the brain are suspended or impaired, and inflate the lungs. so as to iinitate =tura] respiration as nearly as possible." These means should be fully tried, as respira tory action has been restored after more than an hour's suspension. 3lr, Holmes addi tionally recommends cold affusion, stimulating enemata, and stimulants by the mouth; .-and recovery (Ile states) is apparently hastened by the administration of tonics, especially ' 4111i nine, and gentle action on the skin by means of baths.
(Fr. paratonnerre, Ger. Blitzableiter). The principle of the lightnilag conductor is that electricity, of two conducting passages, selects the better; and that when it has got a sufficient conducting passage, it is disarmed of all destruc lye energy. If a person holds his hand near the prime conductor of a powerful electric machine in action, he receives long forked stinging sparks, each of which causes a very sensible convulsion in his frame. But if he holds in his hand a ball, connected with the -rround by a wire or chain, the above sensation is scarcely, if at all, felt as each spark 'occurs, for the electricity, now having the ball and wire passage to the ground, prefers It to the less conducting body. If, instead of a ball, a, pointed rod were used, no sparks would pass, and no sensation whatever would be felt. The point silently discharges the prime conductor, and does not allow the electricity to accumulate in it so as to pro ghee a spark; and the quantity passing at a time, even supposing the rod disconnected with the ground, is not sufficient to affect the nerves. If for the prime conductor of
the machine we substitute the thunder-clouds; for the body, a building; for the convul -sive sensation, as the evidence of electric power, heating and other destructive effects; for the ball, or rod, and wire, the lightning-conductor, we have the same conditions •exhibited on a larger natural scale. It is easier, however, to protect a building from the .attacks of lightning than the body front the electric spark, as the rod in the one case is A much better conductor, compared with the buildinff, than it is compared with the bodv, and, in consequence, more easily diverts the eleciricity into it.
The lightning-conductor consists of three parts: the rod, or part overtopping. the building; the conductor, or part connecting the rod with the ground; and the part in ; the ground. The rod is made of a pyramidal or conical form (the latter being prefera ble), from 8 to 30 ft. in height, securely fixed to the roof or highest part of the building. .Gay-Lussac proposes that this rod should consist, for the greater part of its length below, of iron; that it should then be surmounted by ft short sharp cone of brass; and that it should finally end in a fine platinum needle, the whole being riveted or soldered tomether, so as to render perfect the conducting connection of the parts. The difficulty .o?constructing such a rod has led generally to the adoption of simple rods of iron or copper, whose points are wilt, to keep them from becoming blunt by oxidation. It is of the utmost importance tha't the upper extremity of the rod should end in a sharp point, because the sharper the point the more is the electrical action of the conductor limited to the point and diverted from the rest of the conductor. There is thus less danger of the electricity sparking from the conductor at the side of the building into the building itself. Were the quantity of the electricity of the clouds not so enormous, the pointed Tod would prevent a lightning-discharge altogether; but even as it is, the violence of tlte lightning-discharge is considerably lessened by the silent dischargino. power of the point previously taking place. Accordino to Eisenlohr, a conical rod, eft. in height, ought to have a diameter at its base of 13.elines, and one of 30 ft. a diameter of 26.6 lines.