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Rh not by the chemist. Without detracting from the present value of biological methods, we can not believe that they can replace chemical examination for a long time yet; it must first become certain that all the evil effects of impure water arc due to the organisms now so eagerly studied. When the biological examination of water has been placed on a firm basis, it will then be necessary to carry out the work begun by Professor Mallet, of discovering the chemical characteristics which belong to waters which a biological examination condemn.", and of making the characteristics the basis of future chemical analysis. In the matter of the pollution of streams by sewage, there is much chemical work to be done." Chemistry may be made of service to public health by investigating the actual state of existing evils; in suggesting practical remedies for them; and in the examination of foods and drinks. The education of those who propose to follow these lines of work requires a thorough knowledge of general and analytical chemistry, and of physics. "There is room in the community for a class of persons knowing a little engineering, a little chemistry, a little biology, and a little of other things, an occupation legitimate and honorable, but one which does not justify our calling a person so posted a sanitary engineer or chemist."

Professor Prescott gave the results of experiments in fixing the limits of recovery of certain poisons when mixed with organic matter.

Professor F. P. Dunnington described a method of fixing crayon-drawings, by saturating them with a preparation composed of one part of Damar varnish and twenty-five parts of turpentine. The drawings arc made on unsized manila paper. When dried after treatment, they are ready for use.

Professor Mabery, and the Messrs. Cowles, of Cleveland, Ohio, presented a paper on a new electric furnace and the reduction of aluminum and other metals rare in the metallic state, and the formation of a number of new useful alloys by its aid. Experiments were made in the inquiry for the best means of obtaining a continuous high temperature on an extensive scale. It was found that by introducing coarsely pulverized carbon, mixed with the oxide to be reduced, and applying the electric current, reduction was effected and the temperature was raised to such an extent that the whole interior of the retort fused completely. In other experiments lumps of lime, sand, and corundum were fused, with indications of a reduction of the corresponding metal; on cooling, the lime formed large, well-defined crystals, and the corundum beautiful red, green, and blue octahedral crystals. Following up these experiments, Professor Mabery found that the intense heat thus produced could be utilized for the reduction of oxides in large quantities; and it has already been found that aluminum, silicon, boron, magnesium, manganese, sodium, and potassium, can be obtained from their oxides with ease. Good commercial results have been derived from the application of the process, in the manufacture of aluminum-bronze of various grades, and possessing superior qualities of one kind or another according to the grade; of silicon-bronze, which promises to afford the best material for electric wires; and of boron-bronze, in which boron appears to have almost the same effect when added to copper as carbon when added to iron in the manufacture of steel.

The question, "What is the best initiatory work for students entering upon laboratory practice?" was discussed. Professor H. W. Wiley insisted on the importance of training the novitiates in habits of accuracy—that they should understand at once that chemical science is no guess-work, but a science of definite proportions. Professor R. B. Warder thought it was better to begin with metals than with gases, and Professor F. P. Dunnington suggested a course of metallurgy and assaying. Mr. Thomas Antisell remarked that much depended on the object of instruction—whether it was given only as a part of a liberal education, or with the view of making chemistry a profession. Professor Prescott thought that students should, in analytical work, practice first on known bodies before beginning on unknown; and that too much reliance should not be placed on laboratory work alone, which should be associated with rigid class work in the lecture and recitation rooms. Professor Mabery would have young people begin with common phenomena, master the