392 Notices respecting New Boohs v 



Physics: An Elementary Text-booh for University Classes. By 

 C.Gt.Kxo?T,D.Sc. i FM.S.E. London: Chambers, 1897. 



Some time ago Dr. Knott published an elementary treatise on 

 magnetism and electricity intended chiefly for university medical 

 students in their science year. He now presents a re-issue of that 

 work as a portion of a treatise on experimental physics for junior 

 students, and has added sections on mechanics, heat, sound, and 

 light. The volume is divided into two parts, purely material phe- 

 nomena being discussed in the first part - , which is consequently 

 devoted to mechanics, heat, and sound ; while the second part 

 treats of the aether, and includes magnetism, electricity, and radia- 

 tion. In order to compass the whole subject in the space of 650 

 small pages much compression and some omissions are, of course, 

 necessary, the effects of which are most obvious in the chapters 

 devoted to heat, and especially in the treatment of fusion and 

 evaporation. Some of the statements require revision ; for example, 

 we read on page 229 that " water can be kept liquid at any high 

 temperature by simply heating it in a closed vessel capable of 

 standing the pressure,'"' whereas critical temperature is mentioned 

 and defined on the next page but one. 



A collection of exercises is appended to each chapter and is a 

 good feature of the book ; its usefulness might, however, be in- 

 creased by giving the answers to the numerical problems. J. L. H. 



Theory of Physics. By Joseph S. Ames, Ph.D. New York: 

 Harper, 1897. 



Accoedijto to Dr. Ames three things are necessary in the teaching 

 of physics — a text-book, a course of lectures, experimental demon- 

 strations and tutorial classes, and laboratory work by the students 

 themselves. He believes that the demonstrations and laboratory 

 work afford sufficient instruction in the details of experiments, 

 and a separate text-book may in any case be provided for them. 

 As a supplement to the lectures, however, the student requires a 

 text-book in which the facts of the subject and the explanations 

 of them are arranged in logical order : such a book may, in the 

 opinion of the author, relieve the student from the necessity of 

 taking lecture-notes. The present volume has been written in 

 accordance with these ideas ; almost all points which would be 

 mentioned in a first-year course are to be found in it,, experimental 

 details being altogether omitted. The result is not, as might be 

 expected, a mere cram-book, but a very concise and readable 

 treatise. Perhaps the greatest fault in the book is the suggestion 

 that it should serve instead of lecture-notes, because the taking of 

 notes has an educational value, not only by impressing facts upon 

 the student's memory, but also by training him to observe the 

 relative importance of the various facts and arguments, to which a 



