Page:Popular Science Monthly Volume 13.djvu/266

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254
THE POPULAR SCIENCE MONTHLY.

and does not extend to the whole area of the gulf. Having reached one of these patches, Dr. Streets had a bucket of the water taken on board the steamer, but it was found to be perfectly transparent. But, on sinking the bucket half a fathom or more below the surface, water was brought up which contained the coloring-matter in abundance. "When first drawn up," writes Dr. Streets in the American Naturalist, "and viewed in a glass vessel, by the unaided eye, the water had a faint reddish tinge. When allowed to stand for half an hour, the coloring-matter settled to the bottom of the vessel as a greenish-yellow precipitate; and when some of this was taken up by a pipette and examined under the microscope, it was seen to be composed of minute roundish bodies," the remains of ciliate infusoria, as they were proved to be after much laborious investigation. Under the microscope certain small objects were seen repeatedly darting across the field of vision, when the water was placed fresh upon the glass slide, but they disappeared as quickly as they came, and for a long time it was impossible to tell what had become of them. But at length one of the little bodies stopped directly in the centre of the field of vision and commenced a rapid rotatory movement, which presently ceased, and the animal was quiescent for a second or two; then rupture occurred, the molecular contents oozed out, and the transparent envelope of the organism became invisible. The observation was again and again repeated. The author quotes from Darwin's "Naturalist's Voyage around the World" a passage in which a similar observation is recorded with regard to certain patches of discolored water encountered off the coast of Peru.

Grape-Culture.—To determine the influence of girdling grape-vines on the growth and composition of the grapes, Prof. C. A. Goessmann last year made a series of experiments which are described in the "Proceedings of the American Chemical Society." He had a number of vines girdled during the first week of August, about the time when in the berries of the Concord grape the free acid had attained its highest development, and the grape-sugar was beginning slowly to increase. Entire vines as well as large branches served for the trial. Two incisions from one-eighth to one-quarter of an inch apart were made through the bark and the cambium layer, and the mass between these cuts down to the wood carefully removed. A marked difference in the degree of growth was soon perceived, which persisted during the entire season, until the grapes on the girdled branches had just become ripe. The tests made at this point with both the grapes of the girdled and of the ungirdled branches, grown on the same vine, showed a remarkable difference in the quality of the entire grape and in its relative degree of development. In some instances the girdled branches were two to three weeks in advance of the others. At the close of the season the girdled vines did not show the slightest difference from the ungirdled ones, the place where the bark had been removed being grown over.

Disadvantages of the Health-Lift.—The use of the "health-lift," so called, was under discussion recently in the Philadelphia County Medical Society, and Dr. Benjamin Lee read a paper on the subject, in which he condemned the practice as being neither rational, scientific, nor safe. The paper has been published in the Medical and Surgical Reporter, from which journal we select a few of the objections brought by Dr. Lee against the "health-lift." Exercise, according to Dr. Lee, in order to produce beneficial effects, must extend over a considerable length of time each day, and must be so moderate in its character that such continuance shall not render it exhausting. But it is claimed as the distinctive merit of the "health-lift" that it accomplishes a maximum of exercise in a minimum of time: "Ten minutes a day only is required." That is, "ten minutes a day" to fill the lungs up to their utmost capacity with pure, fresh, oxygenated air, so that every cell may do its duty. "Ten minutes a day" to set in full activity the thousand ducts of the sweat-glands, and to carry off noxious matters out of the blood; to recreate the weary brain-cells; to provoke absorption of the effete materials lying outside of the vessels throughout all the vessels of the body. In the next place, the first requirement of rational exercise is to call into play as far as possible all the muscles;