Chemistry and Physics. 247 



through the book to aid in driving the principles home. The 

 most recent developments in the science also receive adequate 

 attention, the last two chapters being on Hertzian waves and the 

 recent work on the discharge through gases. The demonstrations 

 and deductions are often of the unsatisfactory nature which the 

 necessity of excluding the Calculus makes unavoidable. But 

 aside from this defect, which is inherent in any presentation 

 written for students in a like state of mathematical ignorance, 

 this book appears to the writer to be the most satisfactory one 

 that has come under his notice. l. p. w. 



11. Mechanics, Molecular Physics and Heat. A Twelve 

 Weeks' College Course ; by R. A. Millikan. Pp. 242. New 

 York, 1903 (Ginn & Co.). — This book is a combined text-book 

 and laboratory manual. It represents an attempt to attain a 

 closer coordination between the laboratory, the class room, and 

 the lecture room, and as such is to be highly commended. No 

 one who has taught elementary Physics can fail to be in sym- 

 pathy with this aim or to be interested in the way in which the 

 problem is attacked in the Ryerson Laboratory. The writer can 

 recommend the preface of this book to all who are interested in 

 the very serious problem of how best to teach Physics. 



Judging from personal experience with students of the maturity 

 implied, it would seem as if too much knowledge were assumed. 

 Neither velocity nor mass are explicitly defined. The logical 

 sequence of the development of the principles of mechanics is not 

 all that could be desired. On the other hand, the selection and 

 arrangement of the experiments and problems is excellent. On 

 the whole it would seem that while the book is well adapted to 

 the system of instruction in use at Chicago, its usefulness else- 

 where will be limited — unless that system comes to be generally 

 adopted. l. p. w. 



12. Treatise on Thermodynamics / by Max Planck. Trans- 

 lated by Alexander Ogg. Pp.xii + 272. New York (Longmans, 

 Green & Co.) . — This is an excellent translation of Professor Planck's 

 well-known work on thermodynamics which appeared in 1897, 

 embodying in a connected treatment of the subject the author's many 

 original contributions to this branch of science. Like all of 

 Planck's work, it is marked by strict and satisfactory logical 

 development and by a clear recognition of the nature, authority 

 and limitations of our knowledge of the general principles upon 

 which the science is based. The treatment of the Second Law, 

 while essentially the same as that employed by Clausius, Kelvin 

 and Maxwell, is, at the same time, original in its point of view 

 and is very illuminating ; it should not be neglected by any 

 serious student of thermodynamics. Irreversible processes receive 

 a larger share of attention than is usual — a most commendable 

 feature in a text-book since all actual thermodynamic processes 

 are irreversible, and it is, therefore, very essential that the knowl- 

 edge of the working physicist and engineer should not be con- 

 fined to the ideal reversible case. The book also gives a large 

 amount of space to the discussion of the applications of thermo- 

 dynamics to the problems of chemical equilibrium and it should 



