932 



SCIENCE. 



[N. S. Vol. III. No. 78. 



the student when the subject treated is a 

 branch of pure or applied science. And the au- 

 thor who neglects to avail himself of this simple 

 method of enormously increasing the value of 

 his book does grievous injustice to his subject, 

 his readers and himself. No engineer can be a 

 man of one book. The profession needs a broad 

 and deep foundation. Outline treatises, sched- 

 ules, abstracts from lecture courses and pocket 

 manuals are valuable in their way, but they 

 should be used only as guides to a systematic 

 course of reading or as memoranda in which 

 are collected the results of previous study. 



No one probably knows the truth of these 

 statements better than Prof. Crocker, and with- 

 out doubt it is his recognition of the impossi- 

 bility of making a complete presentation of his 

 subject which has inclined him to supplement 

 his text with so many valuable references. It 

 is in this connection that the chief criticism 

 upon this work is to be made. The sub-title, 

 'A Practical Exposition of the Art for the Use 

 of Engineers, Students and Others interested 

 in the Installation or Operation of Electrical 

 Plants,' might fairly lead one to look for an 

 encyclopedia or library even. The book is 

 rather overloaded by its title. 



The author has made excellent choice of his 

 matter. The book is remarkably free from 

 ' padding ' and as we should expect in a work by 

 Prof Crocker, the form in which the topics are 

 presented is direct and clear. 



Like Oliver Twist, however, the reader is 

 often inclined to ask for more of the same sort. 



The student or engineer will find it helpful, 

 if not complete. And we venture the assertion 

 that the general reader and the ' ' Others inter- 

 ested in the Installation and Operation of Elec- 

 trical Plants ' will find this on the whole the 

 miost satisfactory work published. 



A. S. Kimball. 



WoECESTEE Polytechnic Institute. 



Our Native Birds of Song and Beauty. By H. 

 Nehrling. 4°. George Brumder, Milwau- 

 kee. Part XIV. June, 1896. 

 Again it is our pleasant duty to announce the 

 appearance of another part of Nehrling's meri- 

 torious work on North American Birds. 



It opens with an excellent colored plate of 



the Dickcissel bj"^ R. Eidgway. The male is 

 singing in a field of red clover, with the mother 

 on her nest below. Another plate by Goeriug 

 shows the meadow lark and the bobolink, and 

 also the yellow-headed and red-winged black- 

 birds. The text treats of these species and also 

 of several of the true orioles — Audubon's, 

 Scott's, the hooded, orchard and Baltimore. 

 The biographies, as in previous parts, take one 

 into the woods and fields and marshes, where 

 the birds live, and introduce him to the sur- 

 roundings before bringing in the subject of the 

 sketch. The matter on geographic distribution 

 has received a little more attention than usual, 

 and considerable information is given on food 

 habits. 



The announcement is made that two more 

 parts will complete the present (2d) volume. 

 This is good news, and we heartily commend 

 the book to those who wish to procure, at a 

 reasonable price, a reliable work, with colored 

 plates, on the haunts and habits of North 

 American birds. C. H. M. 



Die Havstiere und ihre Bezeilmngen znr Wirt- 

 schaft des Menschen. Eine geographische studie, 

 VON Eduaed Hahn. Leipzig, Duncker & 

 Humblot. 1896. 8°, pp. 581. 

 In this work the author has brought together 

 in convenient form a large mass of facts con- 

 cerning domesticated animals. He begins with 

 the dog and ends with fish. Besides the ordi- 

 nary domesticated mammals, he includes the 

 yak, buffalo, deer, camel, lama, rabbit, cavy, 

 and ferret. The number of birds treated is 

 also considerable. 



In dealing with the origin of the various 

 breeds, the author usually quotes eminent au- 

 thorities, rarely advancing views of his own. 

 Footnote references are given in profusion, so 

 that those interested in following up the sub- 

 ject shall not want for material. 



The systematic part of the work, in which 

 each animal is discussed at length, is followed 

 by a geographical study, in which the several 

 countries are discussed with respect to their do- 

 mesticated animals. C. H. M. 



The Ginmj Moth. A Eeport of the Work of 

 Destroying the Insect in the Commonwealth 



