THE POPULAR SCIENCE MONTHLY.
ably true that those which are sent by the manufacturers are carefully selected and therefore far more reliable than the average of those sold without certification. Nevertheless, the testers are obliged to reject twenty-five, fifty, and even seventy-five per cent of those sent them. As a rule, these are not rejected without receiving double the time and care required by the large majority of those to which certificates are granted.
The course of instruction in naval architecture recently established at the Massachusetts Institute of Technology provides for a thorough training in the theory and methods of devising and building ships, together with a study of the properties requisite for safety and good behavior at sea. It is arranged to occupy four years, and leads to the degree of Bachelor of Science. It is intended to cover the same ground and accomplish the same results as the English and French Government schools for training naval constructors, and to give, in addition to professional and technical training and equipment, a good scientific and liberal education.
Hitherto disorders observed among workmen in hemp have been regarded as originating wholly in mechanical causes, as in the inhalation of vegetable dusts. Dr. L. Salomon, of Savigné l'Evêque, France, who has studied two cases of such disorders, attributes them to intoxication by the active principles of hemp, similar to those produced by hashish.
The Laboratory of the Psychological Institute at the University of Göttingen—described by Prof. W. O. Krohn as in many respects the best for research work in Germany owes its excellent equipment to a liberal gift from a private person, the state contributing only a pittance to its support. This person is a former student of Prof. Müller.
The Report of the Division of Entomology (Bulletin No. 29) on the Boll Worm of Cotton (Heliothis armiger) covers in the first part observations made by Mr. F. W. Mally upon the parasites and natural enemies of the insect, and presents in the second part bacteriological experiments made by the same observer with certain insect diseases affecting it. The paper also contains observations of the depredations of the larva upon corn, and upon the use of com as a trap for it.
The courses of instruction in the Department of Geology of Colgate University, while designed to give such knowledge of the several subjects as a scheme of general education requires, are so arranged as to provide two years of continuous work to those who may wish to teach geology or pursue it as a profession. The instruction is given by lectures, with text-books for supplementary reading, oral and written reviews, and laboratory and field work. Besides the general collections of minerals, and in geology a dynamical collection, illustrating weathering, glacial action, the work of springs, underground waters and the ocean, the results of volcanic and mountain-building forces, the work of organisms, and various structures, with specimens illustrating lithology, and a systematic collection of fossil remains have been begun. In economic geology sample blocks of building stone have been acquired.
The death is announced of M. Daniel Colladon, of Geneva, one of the most eminent of the former generation of physicists, in the ninety-second year of his age. He was born at Geneva in 1802; became an engineer; studied physics and mathematics in Paris; returning to Geneva, performed in co-operation with Sturm, in 1827, his famous experiments on the propagation of sound in water. The two also studied together the resistance of materials and the compressibility of liquids. In 1829 he became Professor of Mechanics in the École Centrale des Arts et Manufactures in Paris; later, professor in the academy at Geneva. Near the beginning of his career he studied the properties of liquid veins, and executed the remarkable experiment of the transportation of luminous waves by a column of water, which is the basis of the curious luminous fountains. One of his most important discoveries was that of the use of compressed air as a medium for the transmission of energy a discovery which has found practical application of great value in apparatus for perforating tunnels. He was also an earnest student of meteorological phenomena, and made many observations on lightning and hail. Like most students of broad minds, he took much interest in the popularization of science.
Henry J. Philpott, a writer who had gained considerable distinction in the discussion of economical subjects, died of consumption in Niles, Cal., September 24th. He was a resident of Iowa; had been engaged in editorial work in that State; and had gone to California as a last resort for the possible benefit of his health. He was prominent in the organization of the Free-Trade movement in Iowa; was interested in the work of the Society for Political Education of this city; and published many bright and forcible papers on the subjects he held near at heart. He contributed to The Popular Science Monthly articles or letters on The Joint-Snake Idiocy (vol. xxx); Social Sustenance (vol. xxxi); Origin of the Rights of Property (vol. xxxv); Irrigation of Arid Lands, and A Novel Water-Cooler (vol. xxxvi); A Little Boy's Game with a Ball (vol. xxxvii); and Almond Culture in California (vol. xli).