ends to ravel. The Glen is flexible : it conforms to uneven surfaces. The Glen is easily handled : it can be rolled or folded. The Glen is made in all sizes and special shapes. The Glen means cleaner homes. ASK FOR THE GLEN AT ANY HARDWARE STORE Agents wanted in all sections. Write us, Dept. G, for particulars and terms. Our market is in every home McKJNNEY MANUFACTURING CO. PITTSBnRG, PENK., TT.S.A. Chemistry and its Relations to Daily Life By LOUIS KAHLENBERG and EDWIN B. HART Professors of Chemistry in the University of Wisconsin Chth, i2mo, illustrated, jgj pages. List price. *y.^5 If the contributions of chemical science to modem civilizattOJi were suddenly swept away, what a blank there would be ! li^ on the other hand, every person were acquainted with the elements ol chemistry and its bearing upon our daily life, what an uplift humai efficiency would receive ! It is to further this latter end that this book has been prepared. Designed particularly for use by students of jfgriculture and home economics in secondary schools, its use will do much to increase the efficiency of the farm and the home. In the language of modern educational philosophy, it '^ functions in the life of the pupil." Useful facts rather than mere theory have been emphasized, although the theory has not been neglected. The practical char- acter of the work is indicated by the following selected chapter headings : • IL The G)mposition and Uses of Watet* IV. The Air, Nitr ogfen. Nitric Acid, and Ammonia* DL Carbon and Its Compounds* XIL Paints, Oils, and Varnishes* XIIL Leather, Silk, Wool, Cotton, and Rubber* XV* Commercial Fertilizers* XVL Farm Manure* XX* Milk and Its Products* XXL Poisons for Farm and Orchard Pests* THE MACMILLAN COMPANY 64-66 FIFTH AVENUE BOSTON NEW YORK CITY DALLAS CHICAGO ATLANTA SAN FRANCISCO Practical Physics By N. HENRY BLACK of the Roxbury Latin Schoo; Boston, and Professor HARVEY N. DAVIS of Harvard University. Chth, ismoj illustrated^ 488 pages. List price, tr.2^ " In preparing -this book," say the authors in the Preface, " we have tried to select only those topics which are of vital interest to young people, whether or not they intend to continue the study of physics in a college course. " In particular, w^ believe that the chief value of the informational side of such a course lies in its applications to the machinery of daily Ufe. Everybody needs to know something about the working of electrical machinery, optical instruments, ships, automobiles, and all those labor-saving devices, such as vacuum cleaners, fireless cookers, pressure cookers, and electric irons, which are found in many American homes. We have, therefore, drawn as much of our illustrative material as possible from the common devices in modem life. We see no reason why this should detract in the least from the educational value of the study of physics, for one can learn to think straight just as well by thinking about an electrical generator, as by thinking about a Geissler tube. . . ,

AI-modernized reading of the original text

ends to ravel. The Glen is flexible : it conforms to uneven surfaces. The Glen is easily handled : it can be rolled or folded. The Glen is made in all sizes and special shapes. The Glen means cleaner homes. ASK FOR THE GLEN AT ANY HARDWARE STORE Agents wanted in all sections. Write us, Dept. G, for particulars and terms. Our market is in every home McKJNNEY MANUFACTURING CO. PITTSBnRG, PENK., TT.S.A. Chemistry and its Relations to Daily Life By LOUIS KAHLENBERG and EDWIN B. HART Professors of Chemistry in the University of Wisconsin Chth, i2mo, illustrated, jgj pages. List price. *y.^5 If the contributions of chemical science to modem civilization were suddenly swept away, what a blank there would be ! li^ on the other hand, every person were acquainted with the elements ol chemistry and its bearing upon our daily life, what an uplift humai efficiency would receive ! It is to further this latter end that this book has been prepared. Designed particularly for use by students of jfgriculture and home economics in secondary schools, its use will do much to increase the efficiency of the farm and the home. In the language of modern educational philosophy, it '^ functions in the life of the pupil." Useful facts rather than mere theory have been emphasized, although the theory has not been neglected. The practical character of the work is indicated by the following selected chapter headings : • IL The G)mposition and Uses of Watet* IV. The Air, Nitrogen. Nitric Acid, and Ammonia* DL Carbon and Its Compounds* XIL Paints, Oils, and Varnishes* XIIL Leather, Silk, Wool, Cotton, and Rubber* XV* Commercial Fertilizers* XVL Farm Manure* XX* Milk and Its Products* XXL Poisons for Farm and Orchard Pests* 64-66 FIFTH AVENUE BOSTON NEW YORK CITY DALLAS CHICAGO ATLANTA SAN FRANCISCO Practical Physics By N. HENRY BLACK of the Roxbury Latin Schoo; Boston, and Professor HARVEY N. DAVIS of Harvard University. Chth, ismoj illustrated^ 488 pages. List price, tr.2^ " In preparing -this book," say the authors in the Preface, " we have tried to select only those topics which are of vital interest to young people, whether or not they intend to continue the study of physics in a college course. " In particular, w^ believe that the chief value of the informational side of such a course lies in its applications to the machinery of daily Ufe. Everybody needs to know something about the working of electrical machinery, optical instruments, ships, automobiles, and all those labor-saving devices, such as vacuum cleaners, fireless cookers, pressure cookers, and electric irons, which are found in many American homes. We have, therefore, drawn as much of our illustrative material as possible from the common devices in modem life. We see no reason why this should detract in the least from the educational value of the study of physics, for one can learn to think straight just as well by thinking about an electrical generator, as by thinking about a Geissler tube. . . ,

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