LITERARY NOTICES. 



851 



those on the external conditions of plant 

 life and the marine biological stations of 

 Europe. The book is well illustrated and 

 contains an appendix upon the work of the 

 laboratory. 



Pkeparatort Physics. By William J. 

 Hopkins. New York : Longnians, Green 

 & Co. Pp. 147. 



The author of this laboratory manual is 

 Professor of Physics in the Drexel Institute, 

 Philadelphia, and the course of experiments 

 here presented has grown out of the needs 

 of his classes in beginning their study of the 

 science. The greater part of the experi- 

 ments relate to mechanics, for the author 

 regards this subject " as being fundamental, 

 particularly susceptible of treatment in this 

 manner, with comparatively simple appara- 

 tus ; and because the student is very great- 

 ly aided in thoroughly comprehending its 

 problems by investigating them experiment- 

 ally." Besides mensuration, the matters in- 

 vestigated under the bead of mechanics are 

 the composition of forces and of motions, 

 levers and pulleys, breaking strength of a 

 wire, deflection of beams, the inclined plane, 

 the pendulum, etc. The properties of liquids 

 are quite fully illustrated, and the book in- 

 cludes also a few experiments on heat, sound, 

 light, and magnetism. The author main- 

 tains that only quantitative work is of value 

 to the beginner in physical experimentation 

 find he prefers to avoid those subjects in 

 which only discouragingly inaccurate results 

 are obtainable with the methods and appa- 

 ratus that the beginner can use. 



Manual of Physico-chemical Measure- 

 ments. By WiLHELM OsTWALD. Trans- 

 lated by James Walker, Professor of 

 Chemistry in University College, Dundee. 

 New York : Macmillan & Co. Pp. 255. 

 Price, .$2.25. 



Dr. Ostvtald has now added to his valu- 

 able chemical works one on the border land 

 between chemistry and physics. It deals 

 with microscopic measurements of length, 

 accurate weighing, the use of thermometers, 

 thermostats, and calorimeters, of barome- 

 ters and manometers, processes for deter- 

 mining volumes and densities, optical and 

 electrical measurements, determinations of 

 solubility, etc. The author confesses to " a 

 special pleasure in ' pottering ' and making 



things for myself," and urges his fellow- 

 workers to adopt the practice of working 

 with homemade apparatus. To facilitate 

 their doing so he includes in this volume 

 directions for making a logai-ithmic slide- 

 rule, for marking scales on glass, and for 

 soft and hard soldering, giving also a special 

 chapter on glass-blowing. By these means 

 he has " striven to combat that helplessness 

 nowadays so prevalent among experimenters, 

 who have to resort to thi? mechanic for every 

 trifle." A section on weight-testing and sev- 

 eral tables have been reprinted by permis- 

 sion from Kohlrausch's Physical Measure- 

 ments. The tables in the volume comprise 

 only those that are absolutely essential, the 

 work of Landolt and Bornstein being re- 

 ferred to for all others. 



A commendable feature in the System of 

 Physical Culture, prepared expressly for 

 public-school work by Louise Preece (C. W. 

 Bardeen, Syracuse, N. Y.), is that every ex- 

 ercise can be taken by the pupils when 

 standing in the aisles beside their seats. 

 The conditions are prescribed for the exer- 

 cises that the work should be such as will 

 appeal to the sense of the beautiful, combin- 

 ing strength and freedom of movement ; that 

 it must be such as can be done by the pupils 

 in the schoolroom within the usual limita- 

 tions of space and time ; that the movements 

 shall be such as can be conducted in a sys- 

 tematic, orderly manner, without causing 

 confusion ; and that they must be such as 

 do not demand a change of dress. The di- 

 rections are analyzed and arranged by Louise 

 Oilman Kielv, of the University of Minne- 

 sota, and illustrated by the author with 180 

 graceful half-tones and 50 cuts. (Price, $2.) 



In his paper on the Status of the Mind 

 Problem, selected from a course of lectures 

 delivered before the Anthropological Society 

 of Washington, Lester F. Ward compares 

 the old metaphysical and the modern scien- 

 tific methods of mind-study, and ai-gues in 

 favor of the latter. In this method mmd is 

 considered as an attribute of the physical 

 structure. If the charge of materialism is 

 applied to this view, the author answers 

 that, using the word materialism in its only 

 proper and legitimate sense as postulating 

 the material nature of the mind itself, " the 

 scientific conception, of mind is the farthest 



