274 



THE POPULAR SCIENCE MONTHLY. 



a strong membership, and is doing a good 

 deal of valuable work. The Society has 

 permanent rooms at No. 11 East Fourteenth 

 Street, which are open every evening from 

 eight to ten o'clock. The "Journal of 

 the American Chemical Society," like the 

 "American Chemical Journal," is designed 

 not for the outside world, but for those ini- 

 tiated into the mysterious technicalities of 

 the science. 



Treatise relative to tiie Testing of Wa- 

 ter - Wheels and Machinery. With 

 Various other Matters pertaining to Hy- 

 draulics. By James Emerson. Second 

 edition. Springfield, Mass. : Weaver, 

 Shipman & Co. Pp. 216. 



This book has an interest for manufac- 

 turers using water-power. It seems that 

 not long ago the testing of water wheels, 

 with a view to determining their efficiency, 

 was so difficult and expensive an operation, 

 that the proprietors of new patent wheels 

 of all kinds were tempted to make gross 

 exaggerations of their effectiveness, because 

 there were no ready means of getting at the 

 actual facts. The author of this work ac- 

 cordingly addressed himself to the task of 

 finding out some cheaper and more avail- 

 able means of making trustworthy mea- 

 surements. This volume is chiefly devoted 

 to that technical subject, and abounds in 

 pictures of water wheels, and formidable ta- 

 bles. It also gives much information re- 

 garding other forms of mechanism. 



An Outline of General Geology. With 

 Copious References designed for the Use 

 of both General and Special Students. 

 By Theodore B. Comstock, B. Ag., B. S., 

 of the Cornell University. Ithaca: Cni- 

 versity Press. Pp. 82. 



This is a vade meciim for the use of geo- 

 logical students that has grown out of the 

 author's syllabus of elementary lectures, to 

 a mixed class of students, on economic ge- 

 ology and paleontology. It does not profess 

 to be a text-book, but a help to study in 

 connection with such works as Dana's 

 " Manual of Geology " and Le Conte's " Ele- 

 ments of Geology." It gives summaries of 

 important information and many useful ref- 

 erences, blank leaves being freely inserted 

 for convenience in making notes. Such a 

 volume can not fail to facilitate the student's 

 work in various wars. 



Sewer -Gases, their Nature and Origin, 

 and how to protect our Dwellings. 

 By Adolfo de Varona, A. M., LL. B., 

 M. D., etc. Brooklyn : " Eagle " Book 

 Printing Department. 1879. Pp. 166. 

 Price, 75 cents. 



This little book contains much valuable 

 information that every householder in our 

 cities and towns should be familiar with. 

 Many of the worst diseases are now be- 

 lieved to owe their origin to sewer or kin- 

 dred emanations which find their way into 

 houses, through defective planning and 

 workmanship, both of which could be avoid- 

 ed if those most interested would take the 

 trouble to inform themselves on the subject. 

 In the present work the composition of sew- 

 er-gas, as determined by various competent 

 analysts, is first considered ; the relation 

 of these gases to disease is next treated ; 

 then comes a description of the conditions 

 under which sewer-gases are generated, the 

 size, form, and construction of sewers, and 

 the manner in which the sewer is connected 

 with the house : this completes the first part, 

 of the book. The second part is devoted 

 to the subject of the protection of dwellings 

 against the entrance of sewer-poison. The 

 author confines himself to facts and their 

 common-sense applications ; and, although 

 the information which he gives may prob- 

 ably be obtained elsewhere, it is here 

 brought together in a brief and convenient 

 form, and unencumbered with the trash that 

 characterizes so many works on hygienic 

 subjects. The style of binding and display 

 on the cover are hardly in keeping with the 

 contents of the book, but this maybe rem- 

 edied in a future edition. 



Reading as a Fine Art. By Ernest 

 Legouve, of the Academie Francaise. 

 Translated from the Ninth Edition by 

 Abby Langdon Alger. Boston : Rob- 

 erts Brothers. Pp. 1)7. Price, 60 cents. 



A very suggestive and useful little 

 monograph on the subject of reading aloud. 

 The writer believes in an art of reading, 

 which is capable of being generally ac- 

 quired, and he certainly makes out a very 

 good case. He pives the rules for reading, 

 and deals with the philosophy of declama- 

 tion in a very lively and pleasant manner, 

 which has been well rendered in an excel- 

 lent translation. 



