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Page:Popular Science Monthly Volume 15.djvu/588

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THE POPULAR SCIENCE MONTHLY.

center between the primary coils, there is a neutral point or electrical balance, where the electrical phenomena from induction cease to be manifested.

In the "Lancet" we find an account of a meeting of the London Royal Society, at which Dr. Richardson demonstrated the action of the audiometer. He was assisted in this demonstration by Professor Hughes, who, by placing a microphonic key between the battery and one of the primary coils, and by attaching the terminals of the induction coil to the telephone, was able to make the telephone produce sounds whenever he brought the induction coil near to one of the primary coils, and moved the microphonic key so as to make it play on a fine needle suspended in the circuit. "When the induction coil is close to one of the primary coils," says the "Lancet," "the noise is very loud, but as the coil is moved toward the center of the bar the noise diminishes, until it ceases at the center altogether. The scale on the bar is graduated into two hundred degrees, representing units of sound from 200 to zero. At 200 all who can hear at all, can hear the vibration of the drum in the telephone. At zero no one can hear, while between the two points there are two hundred gradations of sound, from the highest down to zero."

A Dog's Affection.—The following narrative is from "Chambers's Journal." Some time ago the late Mr. H—— possessed a collie shepherd-dog, which was very clever at its duty until it had a litter, one of which was spared to it. After this all the poor animal's affections seemed to be centered in her puppy, for she refused, or did most unwillingly, the work she had to do, which so vexed her master that he cruelly drowned the puppy before the mother's eyes, covering the bucket in which he left the body with a sack. He then went round the fields, followed by the old dog, who from that moment resumed her former usefulness. On the master's return in the evening, he bethought himself of the bucket and went to fetch it to empty the contents into a hole which he had made in the manure-heap; he found the bucket covered as he had left it, but on pouring out the contents there was nothing but water. He questioned his wife and other inmates of his house, but they knew nothing about it. The next morning Mrs. H—— was struck with the piteous expression of the poor animal's face, and said to her, "Scottie, tell me where you have taken your puppy." The dog immediately ran off a distance of one hundred yards to the kitchen garden, jumped the fence, and went direct to the farther end of the inclosure to a spot situated between two rows of beans; there, where the earth had apparently been recently moved, she sat, and as it were, wept. Mrs. H—— went again into the house, and without mentioning what had occurred, said to her niece, "Ask Scottie what she has done with her puppy." The question was put, and again the poor creature went through the same performance. These circumstances were mentioned to Mr. H——, who pooh-poohed the idea of there being anything out of the common; but to satisfy his wife he went to the spot and dug down a distance of three feet, and there, sure enough, had the faithful, fond mother buried her little one!

Sympathy in an Ants' Nest.—According to Sir John Lubbock's observations, ants belonging to the same nest never quarrel among themselves; he has never seen any evidence of ill-temper in any of his nests. Again, ants appear to show great kindness to inmates of their own nests which happen to be in straits. In one of Sir John's nests of Formica fusca was a 'poor ant which had come into the world without antennæ. Never having previously met with such a case, he watched her with great interest, but she never appeared to leave the nest. At length one day he found her wandering about in an aimless way, apparently not knowing whither to turn. After a while she fell in with some specimens of Lasius Flavus, who directly attacked her. He rescued her, but she was evidently badly wounded, and lay helpless on the ground. After some time another F. fusca from her nest came that way, examined the poor sufferer carefully, then picked her up and carried her away into the nest. It would have been difficult, Sir John Lubbock thinks, for any one who witnessed this scene to have denied to the ant the possession of humane feelings.