An Important New Textbook for First Year Chemistry GENERAL CHEMISTRY By HARRY N. HOLMES Professor of Chemistry, Oberlin College Cloth, octavo, with figures and diagrams, about 650 pages HE book has been written from the viewpoint of the student. THE It is a text in the full teaching sense of the term, not a reference book. The order of topics adopted has proved satisfactory in actual practice. Chlorine and hydrogen chloride are studied as early as Chapter IX because of the excellent drill they provide both in the classroom and in the laboratory. Treatment of the Periodic System is delayed until two good illustrations of its relations (the halogens and the group comprising sulfur, selenium, and tellurium) have been discussed. Important theories are introduced in chapters dealing with the substances which best illustrate them. Chemical symbols, formulas, and equations-"the tools of the trade"are introduced early. Valence, a rather intangible topic to many students, is given a clear and readily comprehensible introduction. The treatment of Molecular and Atomic Weights has been simplified in order to make it entirely logical and convincing. A notable inclusion is the chapter on Colloid Chemistry. The growing importance of this subject and its natural relation to the study of solutions warrant the prominent place given to it. In a course on "General Chemistry," it is fitting that adequate consideration be given to the elementary facts and principles of organic chemistry. The book contains two able chapters treating of the chief components of carbon. Frequent reference is made to the applications of chemistry in industry, in daily life, and in warfare. A great many exercises and problems are included. These are interspersed through the text, serving to emphasize and illustrate specific points as they arise. THE MACMILLAN COMPANY NEW YORK DALLAS BOSTON CHICAGO Repeated object lessons have demonstrated that nearly all progress in science has resulted in important advances in industry G-E Research Laboratory Schenectady, N. Y. Among the many products developed by the General For further information address Supply Department, Schenectady Office. General Electric General Office Company LABORATORY RUBBER TUBING MADE ESPECIALLY FOR LABORATORY WORK AND DISTINCTLY SUPERIOR TO STOCK RUBBER TRADE TUBING an acid cured, bloomless stock is required. Inside diameter, mm... 46199. Rubber Tubing, A. C. Pure Gum, thick wall. Made from semi-transparent, pure gum sheet without coloring material. It is acid cured, i.e., without "bloom," and is the best tubing obtainable for purposes in which Thickness of wall, mm.. Per ft.... 20 per cent. discount in cartons of 10 ft. 46203. Rubber Tubing, F. S. Pure Gum, thick wall. A seamless, hand-wrapped cloth impression tubing made of the finest grade of Para rubber and sulphur. This tubing is steam-cured and on this account is delivered with a slight "bloom" and is of specific gravity 0.98, i.e., Floating Stock rubber. The hand-wrapping process makes the stock firm and eliminates porosity, while the curing on smooth mandrels makes the bore of the tubing absolutely smooth. F. S. Pure Gum Tubing will last much longer in laboratory work than any acid-sured tubing and is recommended for all laboratory work excepting the few instances where the slight sulphur content might influence determinations. Bore, inches... 1/4 5/16 3/8 1/2 5/8 3/4 Wall, inches.. 1/8 5/32 3/16 1/16 1/16 5/64 5/64 3/32 3/32 7/64 1/8 1/8 25 per cent. discount in cartons of 25 ft. Prices subject to change without notice. ARTHUR H. THOMAS COMPANY WHOLESALE, RETAIL AND EXPORT MERCHANTS LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE PHILADELPHIA, U. S. A. |