LITERARY NOTICES. 



559 



action include both feeling and motion) is so 

 entirely under the control of definite law 

 that the sequence of every thought is fully 

 determined by its correlatives of all kinds, 

 in the sense that it must obey the associated 

 laws of thought and of things. The mind 

 must perceive objects, must know them, and 

 must reason about them legitimately in true 

 accord with its own mental attitude working 

 in correspondence with the organism and the 

 extra-organic world." We have found noth- 

 ing in it clearer than this. 



AN ELEMENTARY MANUAL ON APPLIED ME- 

 CHANICS. By ANDREW JAMIESON. Lon- 

 don : Charles Griffin & Co. 1892. Pp. 

 268. Price, $1.25. 



THIS manual is intended especially for 

 students beginning the subject, and forms a 

 companion to the author's other elementary 

 manuals on Steam and the Steam Engine and 

 Magnetism and Electricity. The subject is 

 treated under four general divisions, the first 

 being devoted to statics or forces in equi- 

 librium, the second to hydraulics and hy- 

 draulic machines, the third to the laws of 

 motion, and the fourth to the properties and 

 strength of materials. 



The book consists of twenty-four lectures 

 delivered by Prof. Jaraieson, to his students 

 and the method of treatment and the or- 

 der of arrangement of the subject matter 

 are based upon the author's experience in 

 teaching. In conformity with this, he has 

 placed the consideration of the laws of mo- 

 tion after that of hydraulics and hydraulic 

 machines, as he finds that it is much better 

 for the student to have some knowledge of 

 simple mechanism before trying to under- 

 stand the abstract laws of motion. Illustra- 

 tive examples are given in each lecture, and 

 a list of suitable questions at the end. 



PRACTICAL ELECTRIC-LIGHT FITTING. By F. 

 C. ALLSOP. London : Whittaker & Co. ; 

 New York : Macmillan & Co. Pp. 275. 

 Price, $1.50. 



THIS handbook should prove of interest 

 and value not only to the practical electric- 

 light fitter, to whom it is primarily addressed, 

 but to the householder using the electric 

 light who desires to take an intelligent inter- 

 est hi the subject as well. The author be- 

 gins his exposition with a brief but clear 

 statement of the meaning and relation of 



current, electromotive force, and resistance, 

 which is quite free from technicalities and 

 understandable by any one without previous 

 knowledge of the subject, and then passes 

 to a consideration of the various appliances 

 and details of construction essential to a 

 complete electric-light outfit. Among the 

 subjects considered are systems of central- 

 station supply, switches, cutouts, incandes- 

 cent and arc lamps and their accessories, 

 electroliers, running of wires, arrangement of 

 circuits in a house, sizes of wires for a given 

 number of lamps, and meters. All these 

 subjects are treated briefly but clearly, so 

 that the ordinary householder can readily un- 

 derstand them. A full statement is given of 

 the rules of the London underwriters, and 

 the work closes with a chapter upon private 

 installations. 



MAGNETISM AND ELECTRICITY. By ARTHUR 

 WILLIAM POYSER, M. A. London and New 

 York: Longmans, Green & Co. 1892. 

 Pp. 382. Price, $1.50. 



THIS very excellent manual is designed for 

 advanced students, and the subject is treated 

 so as to give the student an experimental 

 knowledge, the text being intended to be an 

 aid to the experimental study and not a sub- 

 stitute for it, as is so often the case. 



The main experimental facts of the sci- 

 ence of magnetism and electricity, are set 

 forth by the author, and simple experiments 

 suggested which the student can perform 

 without the use of elaborate apparatus. A 

 chapter is devoted at the close of the book 

 to some of the applications of the principles 

 of the science, in which the telephone, mi- 

 crophone, electric lamps, and the dynamo are 

 briefly described, and a short but instructive 

 account is given of the recent researches of 

 Hertz in proof of the electro-magnetic theory 

 of light of Clerk Maxwell, and those of Tesla 

 with currents of great frequency. 



HEREDITARY GENIUS. By FRANCIS GALTON. 

 London and New York : Macmillan & Co. 

 1892. Pp. 379. Price, $2.50. 



IN republishing this inquiry into the ques- 

 tion whether natural ability is hereditary, Dr 

 Galton has chosen to leave it in much the 

 same form in which it first appeared more 

 than twenty years ago, as to recast it and in- 

 corporate data now accessible would have in- 

 involved greater labor than he could well 



