THE POPULAR SCIENCE MONTHLY.
In consequence of the growing interest in Industrial drawing and of the few facilities in the State for instruction in this subject, the Faculty of Cornell University have consented to receive teachers as special students, and to afford them all the advantage which the university offers in the various departments of drawing. The departments now established are free-hand drawing, mechanical engineering, civil engineering, and architecture. Special students will enter the same classes as the general students, and on the same terms. No one but teachers will be received—no entrance examination will be required, and no diplomas will be given.
The remains of a mastodon were lately found near Elkhart, Indiana, which evidently belonged to a monster specimen, one of the largest yet discovered. The section of a tusk which was unearthed gave evidence of having been about ten feet long. A monster tooth, six inches over the top, exceedingly well preserved, was dug up, and a shoulder-bone, which shows the animal to have been at least twelve feet high. The bones are to be presented to the city Museum Association lately formed at Elkhart. Several large specimens of the remains of mastodons have been found in Elkhart and adjoining counties within the past four or five years.
The German Association of Naturalists and Physicians will assemble this year at Cassel on September 18th, the sessions continuing for one week. Among the addresses promised are the following: "Relations of Darwinism to Social Democracy," by Oscar Schmidt; "Symbiosis, Parasitism," etc., by Prof. De Bary; "The Education of the Physician," by Prof. Fick; "The Color-Sense and Color-Blindness," by Dr. J. Stilling.
We regret to announce the death, at Philadelphia, of William M. Gabb, paleontologist, at the early age of thirty-nine years. His life-work commenced in 1862, when he was appointed as paleontologist on the staff of Prof. Whitney in the Geological Survey of California. In 1868 he visited Santo Domingo and made a survey of that island. He went on a similar mission to Costa Rica in 1873. "His various contributions to science," says the American Journal of Science, "are a great honor to the country, and eminently so to the State of California, for which a large share of his work was done."
Dr. Carl Rokitansky, for thirty years Professor of Pathological Anatomy in the University of Vienna, died in that city on July 23d, aged seventy-four years. His greatest work, a "Manual of Pathological Anatomy," was translated into English, and published in London by the Sydenham Society.
The death of Admiral Sir George Back is announced, aged eighty-one years. Back entered the naval service of Great Britain in 1808, and the following year was taken prisoner by the French, and held in captivity till 1814. In 1819 he did noble service with Franklin in exploring the extreme northernmost coast of America. His perseverance and his fertility of resource on that expedition were above all praise. In 1825 he again visited the arctic regions under the same commander. On both of these expeditions the explorers were rescued from death in the inhospitable north by the heroic exertions of Back. He commanded polar expeditions in 1833-'35 and 1836-'37.
The Commissioner of Agriculture has recently appointed Prof. J. H. Comstock, of Cornell University, and Prof. A. R. Grote, of Buffalo, New York, director of the Buffalo Society of Natural Sciences, as special examiners, under the direction of Prof. C. V. Riley, entomologist of the department, in an investigation now being initiated of the insects injurious to the cotton-plant. Several local observers in various parts of the South have also been appointed, and it is the intention of Prof. Riley to make a complete report on all insects affecting the Southern staple and the best means of counteracting their injuries, that shall be to the people of the South what the report of the entomological commission on the Rocky Mountain locust is to the people of the West. The department is especially fortunate in securing the services of Prof. Grote for this undertaking, as he has already given the subject much attention, and has carefully worked out the life-history of the cotton-worm, one of the worst enemies of the cotton-plant. The results of these investigations are contained in a paper read at the Hartford meeting of the American Association for the Advancement of Science, and published in the "Proceedings" of that year.
To ascertain the influence of light upon cement, Heinzel divided into three portions a lot of cement, and exposed one of these (A) to the air and full light, another (B) to the air and diffused light, and secluding the third (C) in darkness from the air. After six months it was found that A made a weak mortar by absorbing 38 per cent, of its weight in water, and it had become friable; B with 333 per cent, of water made a mortar too adhesive to the trowel, and it yielded up some of its water; C with 332 per cent, of water made an excellent mortar, easily stirred and flowing, and it parted with some of its water. After setting for twenty-eight days, the relative strengths were A 3, B 37.9, C 44.6.