Page:Popular Science Monthly Volume 23.djvu/440

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tempted their scientific classification in his fourteenth year. At the same time he was interested in other branches of science and collections. In 1872 he spent three months in the mountains of Colorado with Dr. C. C. Parry; in 1873, five months as meteorologist to Captain Jones's Yellowstone expedition. The next year he spent chiefly in Colorado, completing a series of expeditions in which he collected altogether 25,000 specimens of insects, many of them very rare. From 1869 he was one of the most active and useful members of the Davenport Academy, and was in succession its recording secretary, corresponding secretary, and president; and he sustained a large share of the burden of the editorial supervision and publication of its "Proceedings." Mr. Putnam's scientific publications were not voluminous. With one or two exceptions his most important investigations were never fully elaborated, and were embodied only in notes, letters, and incomplete manuscripts. A list of twenty-one is given, of which the most valuable are papers on bark-lice, and on his investigations of the Salpugidæ, a group intermediate between the scorpions and the spiders. A paper by him on "Insects and Flowers of Colorado" was published in the tenth volume of "The Popular Science Monthly."

Getting Water in the Desert.—The supply of water always formed a principal question, and often a preponderant one, during the marches of the French troops in Algeria and Tunis. Rivers having a permanent supply of water are very rare in those countries, but wadies—beds of torrents, generally dry, but full after a shower are numerous. The most ordinary supplies of water were sedirs, or puddles of rain-water held in natural basins of clay or stone, near which the camps were pitched whenever they were accessible. They are to be found in the beds of wadies, and sometimes in slight depressions of the plain, where they are frequently of considerable extent. When full they contain, notwithstanding they are so shallow, prodigious quantities of water, which is, however, exposed to an enormous evaporation, so that it does not last long. These natural reservoirs have been covered with sand in many places, where a permeable bed several feet high has been formed, with a dry surface corresponding with the general level of the surrounding land. It is only necessary to dig a hole, and wait a little while, for the water to rise to a certain level, forming a kind of extemporaneous well, which the Arabs call an oglat. These wells contain but little water, and are soon dried up when drawn from, but will become filled again in the course of a few hours. These resources, precarious at the best, are often wanting; but the country is full of ruins, attesting the former existence of a large population, and among them are many useful structures, including well-made cisterns still almost entire, and very deep. Water is got from them by going down steps to the surface, or by means of a device called the guerber, which is in general use. This is a leathern bottle, adjusted at the curb of the well by means of pulleys and ropes, which are worked in such a manner by a man and an ox that the vessel goes up and down, fills itself with water and empties itself, without any one having to handle it directly.

Symptomatic Anthrax and Disinfectants.—The Lyons "Médicale" publishes the results of some valuable experiments which have been made by MM. Arloing, Cornevin, and Thomas, on the influence of various disinfecting agents on the virus of symptomatic anthrax. If the contents of a tumor in this disease be allowed to dry slowly at a temperature of 35° Cent, (or 95° Fahr.), a residue is obtained in which the organisms of anthrax retain their full activity. Water, through which a little of the residue is diffused, has a virulence not inferior to that possessed by the fresh virus, and which continues for at least two years. It was found, in carrying on the experiments, that the resisting power of the dried virus is much greater than that of the fresh. Whatever destroys the dried is capable of destroying also the fresh virus, while the converse is not true. The following substances were found to have no effect even upon the fresh virus: alcohol saturated with camphor or carbolic acid, glycerine, ammonia, acetate and sulphate of ammonia and sulphate of ammonium, benzine, a saturated solution of chloride of sodium, quicklime and lime-water,