It is comparatively but a short time since that people were marvelling at the telegraph, and the newspapers used to write gushingly about ‘compelling the lightning to bear our messages,’ and all that sort of thing. I dare say many boys who read this can remember what a sensation the electric light made when displayed on the top of one of the buildings in the Strand—they need not be very old boys to have seen it there. Nobody would be very much attracted by such a light anywhere now.
There is scarcely a single art, manufacture, or science into which electricity has not been pressed to do good service. Electric lighting has become a matter of course, both indoors and out; and, while it has been proposed to annihilate night in the city of Washington by setting up four huge electric ‘suns’ on the hill of the Capitol, so rendering any other illumination in the streets and houses as unnecessary as in the day-time; a modified lamp of a few ‘candle-power’ has recently been devised for small rooms, supplied by a little battery which might stand on the mantel-piece. Tennis is played and photographs are taken by the electric light; electric bells are as common as door-knockers; electricity is proposed as a means of killing sheep and bullocks in the slaughter-house and criminals on the scaffold, and is used by the physician as a remedy for the preservation of life.
On board some of our great men-of-war the captain can sit in his cabin and not only see the position of the helm, the speed of the ship, and the direction in which she is steering, but can fire every gun she carries—all by electricity. Electricity springs the deadly mine on the field of battle, and animates a sixpenny toy sold in the Lowther Arcade. Even the railway engines, tram-cars, and screw-boats propelled by electric force which have been lately invented cause but little surprise now, so habituated have we become to the gigantic strides of this nineteenth-century infant!
I am not going to preach a sermon upon it, however, as you may be expecting from this terrific introduction; nor am I going to bore you with a lecture on coils and currents and poles and induction, or any other technical details. But it occurs to me that a brief mention of one or two of what may be termed the minor applications of electricity—one or two only out of thousands—will perhaps interest you, as illustrating how widely spread the influence of the science has become, and how it penetrates into nearly all the affairs of life. To my mind, the fact of telegraph and telephone wires stretching for hundreds of miles across uncleared jungles and through virgin forests, as they do, is not half so strong an evidence of the pitch to which it has arrived as its being adapted to a conjuring trick.
At one of the places of amusement in Paris some ‘sprites’ carry wands which sparkle out and fade again as required, flashing in time to the music. But a much prettier and more elaborate arrangement has been brought out since, though I believe it has not yet been presented to the public. The performer—magician, fairy, or whatever he or she may be—wears a fancy dress, which is embroidered all over with what look like large glass beads or imitation pearls. These are in reality tiny electric lamps, all connected with each other by wires covered with silk in the texture of the dress, and communicating with two little iron plates in the heels of the fairy’s boots. Nothing remarkable, of course, is seen until these two iron discs come into contact with a certain spot—which is reached just at the appropriate moment—when every bead bursts into dazzling light, and the fairy becomes clothed with white living fire in an instant! Then she steps away from the communication with the batteries below, and the beads are as suddenly dead again.
Electric alarums for the detection of burglars have long been in vogue in the shape of bells and gongs, so arranged as to be sounded directly the fastening of a door or window is tampered with, and electric ‘booby-traps’ have even been tried, designed to give the thief a severe shock or take him prisoner—the result generally being that the master of the house or the servants get caught in the snare themselves half-a-dozen times, after which its use is discontinued.
The weak point in all these things has been that, from their costly and intricate nature, they could not conveniently be applied to every accessible situation, and that the mechanism was always liable to be thrown out of order. The burglars would carefully avoid meddling with the shutters and doors to which these appliances were known to be affixed, and would gain an entrance at some unprotected spot. Now, however, somebody has patented an electric mat, which can be put down anywhere at night, and which sounds an alarm directly an intruder steps upon it.
Galvanism is employed, as is well known, by medical men, to restore power to paralysed limbs, to revive people who are faint almost to death, and to cure diseases. Dentists owe a good deal to electricity, and their patients owe still more. When a surgeon wants to cauterise some very small spot deep down in the flesh, instead of cutting and burning all the way down, he now inserts a wire, which is shielded, except just at the part which will come in contact with the bad place; an electric current is sent through it, and the wire becomes red-hot.
Neater still is the way in which a needle is detected underneath the skin. I dare say you know that such a thing often gives a doctor a great deal of trouble, and it is an accident which you should be very careful to guard against. It frequently occurs to boys who run about the house with bare feet. The needle, having no head like a pin to stop it, slips right into the flesh. Sometimes the patient is not certain whether it is there or not, as it may have worked out again, for the danger in these cases arises from the tendency of the needle to travel through the flesh, doing great mischief as it goes along. What is the doctor to do? If he is quite sure that it is there and can feel it, he will of course cut it out; but he has to be very cautious. A needle is so fine and slender, that sometimes, even when he thinks he can feel it with the point of a probe, he finds himself mistaken. It has been suggested that a magnet hung over the part will turn if any steel lie concealed beneath—a very pretty theory, but one that does not answer when put into practice. But one may make quite certain about it by probing the flesh with a little instrument which is connected with a battery in such a way that directly the point touches metal the circuit is completed and a bell rings.