276 



POPULAR SCIENCE MONTHLY. 



Variation gives the results of further 

 evidence and further thought in that 

 line, qualifying and developing certain 

 views enunciated in the first edition. 

 Various modern ideas are considered 

 under the title Recent Criticisms and 

 Hypotheses. The chapter on The Argu- 

 ments from Embryology has been large- 

 ly rewritten. Smaller additions appear 

 in the form of new sections incorpo- 

 rated in pre-existing chapters. The as- 

 sistance needed in the work of revision 

 has been given by Prof. W. H. Perkin 

 in Organic Chemistry and its derived 

 subjects; Prof. A. G. Tansley in Plant 

 Morphology and Physiology; Prof. E. 

 W. MacBride and Mr. J. T. Cunning- 

 ham in Animal Morphology; and Mr. 

 W. B. Hardy in Animal Physiology. In 

 all sections not marked as new the au- 

 thor desires it to be understood that the 

 essential ideas set forth are the same as 

 they were in the original edition of 1864. 



Prof. Silas W. Holman attempts 

 the presentation, in Matter, Energy, 

 Force, and Work,* of some of the fun- 

 damental ideas and definitions of phys- 

 ics in a plain and logical manner. His 

 purpose is not to set forth the experi- 

 mental side of the subject or to describe 

 phenomena or laws. He rather assumes 

 a slight knowledge of these, and pro- 

 ceeds to develop the concept and defi- 

 nitions. The author regards a clearer 

 thinking on these subjects as of special 

 importance to engineers and members of 

 the other technical professions, because 

 correct views upon them have become 

 essential in those professions through 

 the progress of the applications of sci- 

 ence to the industrial arts. These ap- 

 plications are likewise of considerable 

 interest to the untechnical members of 

 the community. Professor Holman has 

 composed his book with the principle of 

 presenting the subject of physics in 

 logical sequence, and has divided it into 

 two parts, the first of which contains 

 the matter immediately proper to the 

 subject, with discussions of substance 

 or matter, motion; energy and its 

 forms; force; kinetic energy, force- 

 measurements, work, potential energy, 



* Matter, Energy, Force, and Work. A Plain 

 Presentation of Fundamental Phynical Concepts, 

 and of the Vortex-Atom and other Theories. 

 By Silas W. Holman. New York: The Macmil- 

 lan Company. Pp. a.")?. Price, S3.50. 



and matter again, as distinguished from 

 substance. The second part comprises 

 summaries of the chief theories of the 

 nature of matter, force, and energy, in- 

 cluding the kinetic theory of gases, Le 

 Sage's theory of gravitation, the vor- 

 tex-atom theory, and a discussion of 

 the nature of energy and matter, with 

 observations on chemical energy and 

 the ether. 



The Short Course in Music, prepared 

 for use in schools where a complete 

 course is not thought necessary, by F. 

 H. Ripley and Thomas Tappen, is em- 

 braced in two books, of which we notice 

 the second (American Book Company). 

 Familiar songs are made the basis of 

 instruction, some of those which appear 

 as melodies in Book One being repeated 

 liere in full score. All other material 

 has been prepared especially for this 

 book. The music and directions are 

 adapted equally for unchanged and 

 changed voices. Voice training and the 

 elements of phrasing and expression are 

 furnished in a group of solfeggios at the 

 close of the book. Theory is given in 

 condensed form, but one that, it is 

 claimed, embraces all the essential ele- 

 ments of vocal music. 



Mr. J. E. Marr has prepared his ex- 

 position of The Principles of Strati- 

 graphical Geology (Cambridge Univer- 

 sity Press; The Macmillan Company, 

 New York, $1.60), under the belief that 

 an idea of the subject can be obtained 

 most satisfactorily if a large number of 

 the details connected with the study of 

 the stratified rocks are omitted. He has 

 accordingly given very brief accounts 

 of the strata of the difi'erent systems, 

 pajnng more attention to the bearings 

 of the facts than to their enumeration. 

 The history of the earth is presented as 

 a connected one, in which one period is 

 linked on to the next, every event that 

 occurs introducing a new complication 

 into the conditions, which are conse- 

 quently never quite the same — the 

 changes showing an advance from the 

 simple to the more complex. The study 

 proves that an enormous period elapsed 

 subsequent to the formation of the 

 earth and previous to the deposition of 

 the stratified rocks, of which we have 

 only the slightest, if any, knowledge. 

 1 he stratigraphical geologist has to es- 

 tablish the order of succession of the 



