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THE MACMILLAN CO MPANY'S NEW PDBLIGATIONS. 



THE HISTORY OF MANKIND. 



By Professor Feiedkich Eatzel. Translated from the second German edition by A. J. Butlek, M. A. With 

 Introduction by E. B. Tyloe, D.C.L., F.R.S. With 9 Colored Plates, Maps, and upward of 400 Illus- 

 trations. Imperial 8vo, cloth. Vol. I., |4.00. To be completed in 3 vols. Vols. II. and III. in preparation. 



Professor Ratzel's Volkerkunde has for some years enjoyed a wide popularity in Germany. Combining scientific accu- 

 racy with a due legard to the interests of those who read mainly for entertainment, it is undoubtedly the best general his- 

 tory of the di-velopment of mankind which has yet appeared. The present translation has the advantage of being made 

 from the second edition, which appeared, carefully revised and enlarged, so lately as the autumn of 1S94, and mav therefore 

 be regarded as embodying the results of the most recent researches. Nor must it be f >rgotten that if a man of the " nat- 

 ural" races speaks a word of any language but his own, the odds are at lea>-t ten tn one that it is English, and that a work of 

 this kind should, therefore, appeal to English-speaking people in a way that it can hardly do to those of any other race. 



DAILY NEWS. — " The same publishers are rendering a most signal service to the cause of education in its best sense, 

 by their publication of Friedrich Ratzel's Volkerkunde, or History of Mankind." 



NATURA L SCIENCE.—" It is an indispensable book of reference to every student of Ethnology, and it has long been 

 a regret that the absence of an English translation rendered it inaccessible to a large proportion of English travelers. . . . 

 The illustrations, which are an important feature in the original, are being admirab.y produced." 



THE EDUCATION OF THE CENTRAL NERVOUS SYSTEM. 



A Study of Foundations, especially of Sensor and 3Iotor Training. By Eeuben Post Halleck, M.A. (Yale). 

 12mo, cloth, $1.00 net. 



The requisite sensory, motor, and ideational training necessary to secure the proper development of brain cells while 

 their brief morning of plasticity lasts are clearly and concisely set forth in a manner as devoid as possible of technicalities. 

 This is a thoroughly practical work on the subject of the gravest importance for every teacher and parent. 



A HISTORY OF ELEMENTARY MATHEMATICS, 

 With Hints on Methods of Teaching. By Floeian Cajoei, Ph.D., Professor of Physics in Colorado 

 College. Crown 8vo, cloth, $1.50 net. 

 This little book is a popular history of those parts of mathematics which are taught in public schools and high schools. 

 It is intended" for teachers, and aims not only to supply historical information, but also to point out how the study of the 

 growth of mathematics leads to valuable suggestions on methods of teaching it. Among the topics discussed are the various 

 modes of teaching arithmetic and algebra during the last four centuries, the evolution of the Anglo-American arithmetic, 

 the ascendency of Euclid as a geometrical text-book, a critical estimate of Euclid and his modern comnetitors from the 

 standpoint of pedagogy and of exact science. 



NEW VOLUME. 



THE ELEMENTS OF PHYSICS. 



A College Text-Book. By Edward L. Nichols and William S. Feankltn, both of the Department of 

 Physics, Cornell University. Vol. II. Electricity and Magnetism. 8vo, cloth, $1.50 nrf. Already pub- 

 lished. Vol.1. Mechanics and Heat. 8vo, cloth, $1.50 we<. In preparation. Vol. III. Sound and Light. 



The first volume, which was issued about January 1, 1896, is devoted to the subject of Mechanics and Heat, the second lo 

 Electricity and Magnetism, and the third to Sound and Light. No attempt has been made in tb s work to produce a com- 

 plete manual or compendium of experimental physics. The book is planned to be used in connection with illustrated lec- 

 tures, in the course of which the phenomena are demonstrated and described. The authors have accordingly confined 

 themselves to a statement of principles, leaving the lecturer to bring to notice the phenomena based upon them. In stating 

 these principles free use has been made of the calculus, but no demand has been made upon the student beyond that sup- 

 plied by the ordinary elementary college courses on the subject. 



ALTERNATING CURRENTS AND ALTERNATING CURRENT MACHINERY. 



Being Vol. II. of the Text-Book on Electro-magnetism and the Construction of Dynamos. By DuGALD C. 



Jackson, C.E., Professor of Electrical Engineering in the University of Wisconsin; Member of the 



American Society of Mechanical Engineers, the American Institute of Electrical Engineers, etc., and 



John Price Jackson, M.E., Professor of Electrical Engineering in the Pennsylvania State College; 



Member of the American Institute of Electrical Engineers, etc. 12mo, cloth, pp. xvii + 729, $3.50 net. 



A text book for engineering colleges and a reference-book for electrical engineers. The simplest treatment of the 



theory of alternating currents whicli can be considered complete is chosen. The latter part of the book contains a thorough 



discussion of the methods of calculating transformers, alternating current motors, and rotary transformers, with chapters 



on their construction, testing, and operation in service. The book is profusely illustrated by "diagrams and figures. 



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