Page:Popular Science Monthly Volume 13.djvu/652

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THE POPULAR SCIENCE MONTHLY.

left the scale as the corona was brought upon the fine slit by which the tasimeter itself was protected."

 

Progress of the Electric Light.—Progress is being steadily made with the electric light, both in the sense of improving the apparatus needed for utilizing it and in finding for it practical application. In Paris the railway-station Gare St.-Lazare is now very effectively lighted with the aid of the instrument known as Lontin's distributing machine. The contrast between the pure, clear white electric light and the dull-yellow gaslights in the surrounding streets is enough to convince the most skeptical of the superiority of electricity over gas as an illuminating agent. In the Lontin machine ordinary prepared carbon-wicks are employed, which are regulated by a Lontin burner: the light is remarkably steady, and the wicks burn in the open air without globes or shades of any kind. A strong objection to this machine, unfitting it for use in private houses, is the hissing noise it makes when in operation. The electric candle invented by Jobloshkoff is used for illuminating the Place de l'Opéra in the same city. Across the open area of the Place, and extending toward the new Avenue de l'Opéra, there is a double row of large lamp-posts down each side, each surmounted by a large cylindrical lamp of clouded glass, and containing twelve electric candles. The whole space is lighted as bright almost as day. As soon as a candle burns down, another is moved by mechanism into its place without much appreciable disturbance of the general effect. There is no flickering. The great drawback to the Jabloshkoff candle is its costliness, the illumination being as expensive as when gas is used.

 

Bathing as a Cause of Ear-Disease.—Inflammation of the middle ear, often resulting in chronic deafness, is a not infrequent consequence of bathing. The damage, according to Dr. Sexton, in the Medical Record, consists in the admission of water to the ear, either through the external auditory canal or the Eustachian tube. When water finds admittance to the former, if cold or salt, inflammation of the meatus alone may result; or, if violently injected, as in surf bathing, or long retained in the canal from diving, the disease may affect the drumhead and middle ear. Whenever water is forced from the mouth and nostrils into the middle ear through the Eustachian tube, inflammation of the middle ear is almost sure to occur, even though the water be warm. According to the author, several thousand severe cases of aural disease result annually from bathing in New York City alone. The bather, when in the surf, should take the water on his chest or back, with mouth and nostrils closed, and never presenting the ear to the in-coming wave. A firm pledget of cotton-wool in the ears is some protection.

 

The Carpet-Beetle.—Notices have appeared from time to time during the last four or five years of a new carpet-beetle said to be far more destructive than the familiar carpet-moth. This insect has been identified by Dr. J. L. Le Conte as Anthrenus scrophulariæ, a European species. A good account of it is given in the American Naturalist by Mr. J. A. Lintner, who has studied this insect attentively since its first appearance on our shores. The larva, he says, measures at maturity about three-sixteenths of an inch in length, and it is in this stage of its existence that Anthrenus preys upon carpets. A number of hairs radiate from its last segment in nearly a semicircle, forming a tail-like appendage almost as long as the body. The front part of the body, which has no distinct head, is thickly set with short brown hairs and a few longer ones. Similar short hairs clothe the body. The body has the appearance of being banded in two shades of brown, the darker one being the central portion of each ring, and the lighter the connecting portion of the rings. Having attained its full larval growth, it prepares for its pupal change without forming a cocoon, but merely seeking some convenient retreat. Here it remains motionless until it has completed its pupation, when the skin is rent along the back and through the fissure the pupa is seen. A few weeks later the pupal skin is split down the middle of its dorsal aspect, and the brightly-colored wing-covers of the beetle are disclosed. Soon after their emergence from the pupal case during the fall, winter, and spring, the beetles pair and the