710 



THE POPULAR SCIENCE MONTHLY. 



vanced view of it might be expressed as fol- 

 lows : If all the physical forces are but 

 affections of matter, quivering particles of 

 the medium affected, it is easy to see thai 

 the senses, which we find to be special ad- 

 justments of ourselves to these different 

 forces, are merely channels of different 

 kinds of motion leading to the brain. In a 

 word, therefore, the sensation of light is a 

 definite motion of a definite part of the 

 brain. If it were possible to study the lines 

 or areas of motion which a sensation of a 

 given intensity sets up in the brain, or the 

 structural changes which accompany the 

 repetition and combining of different sensa- 

 tions, there would be some hope that the 

 physical or subjective aspect of the law of 

 association could be explained. The differ- 

 ence between the apprehensions of this law 

 by Hartley and Mill is that Hartley, being a 

 physiologist, and moved by the excitement 

 of discovery, endeavored to portray the sub- 

 jective aspect of this law, while Mill devoted 

 himself to its manifestations in the relations 

 and history of life. 



The author has made a great many se- 

 lections from these two writers, which has 

 the effect of bringing their systems into 

 view side by side. He precedes these selec- 

 tions with a biographical sketch of Hartley 

 and Mill, and accompanies them with com- 

 parisons and criticisms of his own, which 

 constitute the greater part of the book. The 

 value of such a book depends, of course, 

 upon the point of view from which the criti- 

 cisms are made, and the skill of the selec- 

 tions. With regard to the latter, but little 

 improvement could be suggested, and, al- 

 though some opportunities have been neg- 

 lected of bringing important points into 

 bold reHef, the criticisms are remarkably 

 just and free from error. 



Text-book OF Experimental Organic Chem- 

 istry FOR Students. By H. Chapman 

 Jones. New York : D. Van Nostrand. 

 Pp. 145. 



The author of this book has added an- 

 other to the already considerable list of use- 

 ful little manuals on practical chemistry. 

 lie confines himself to organic chemistry 

 and has endeavored to make the study of 

 that branch of science more interesting to 

 the quite elementary student than has been 



done by previous authors. The work is not 

 a text-book, but merely a laboratory com- 

 panion for the student, and is, moreover, 

 especially arranged for those who have but 

 a limited time at their command. It is not 

 illustrated, though a good number of simple 

 experiments are described. 



The Botanical Collector's Hand-book. 

 By Professor W. Whitman Bailey. 

 Naturalists' Handy Series, No. 3. Sa- 

 lem, Massachusetts : George A. Bates. 



This is precisely what its name implies. 

 The contents are arranged under the gen- 

 eral headings of Herborizing, Field-Work, 

 Collecting and preserving Fungi, Closet- 

 Work, The Herbarium, Bibliography, Her- 

 baria, and Public Herbaria. 



Under each of these headings much valu- 

 able information for the collector is given. 



PUBLICATIONS IlECEI^^D. 



The Epidermal Organs of Plant? : Their 

 Morphology and Phvsiology. By Charles F. 

 Cox, F. R.M. S. Pp.15. 



A Report on the Teaching of Chemistry and 

 Physics in the United States. By Frank Wig- 

 glesworth Clarke, S. B., United States Bureau 

 of Education. Pp.219. 



" The Tonic Sol-Fa Advocate." Edited by 

 Theodore F. Seward. Vol. I, No. 1. New York: 

 Biglow & Main. Monthly. Pp. 16. 50 cts. a 

 year. 



Annual Report of the Board of Directors of 

 the Chicago Astronomical Society, together 

 with the Report of the Director of Dearhorn 

 Observatory. 1881. Pp. 16. 



Descriptions of some New Tortricidse (Leaf- 

 rollers). By C. V. Riley, M. A., Ph. h. Wash- 

 ington. Pp. 9. 



Some Double and Triple Oxalates containing 

 Chromium. By F. W. Clarke. The Titration 

 of Tartaric, Malic, and Citric Acids, with Potas- 

 sium Permanganate. Preliminary Note. By F. 

 W.Clarke. Pp.7. 



Pliocene Man in America. By James C. 

 Southall, A. M., LL. D.. of Richmond, Virginia. 

 New York : A. D. F. Randolph & Co. Pp. 30. 



Braith waiters Retrospect of Practical Medi- 

 cine and Surgery. Part Ixxxiii. New York: 

 W. A. Towusend. Pp. 276. 



What shall We do with the Inebriate? By 

 T. D. Crothers, M. D. Hartford, Connecticut. 

 Pp.24. 



Ilip-Injuries, including Hip-Joint Disease, 

 and Fractures of the Femoral Neck: Splint lor. 

 By De F. Willard, M. D. Philadelphia. Pp. 4. 



Hip-Joint Disease ; Death in Early Staire from 

 Tubercular Meningitis. By De Forest Willard, 

 M. D. Microscopic Appearances, with Cuts. By 

 E. O Shakespeare, M. D. Cambridge: River- 

 side Press. Pp. 20. 



Fifth Annual Report of the State Board of 

 Health of Wisconsin. 1881. Madison, Wiscon- 

 sin. Pp. 156. 



Catalogue of the Phtenogamous and Vascu- 

 lar Cryptotramous Plants of Michigan, Indige- 

 nous, Naturalized, and Adventive. By Charles 



