SCIENCE. 



Have Just Published 



The Concepts and Theories of Modern Physics. 



The Concepts and Theories of Modern Physics. By J. B. Stallo. " International Scientific Series.' 

 i2mo, cloth. Si. 75. 



"Judge Stallo's work is an inquiry into the validity of those mechanical conceptions of the universe which are 

 now held as fundamental in physical science. He takes up the leading modern doctrines which are based upon 

 this mechanical conception, such as the atomic constitution of matter, the kinetic theory of gases, the conserva- 

 tion of energy, the nebular hypothesis, and other views, to find how much stands upon solid empirical ground, 

 and how much rests upon metaphysical speculation. Since the appearance of Dr. Draper's 'Religion and 

 Science,' no book has been published in the country calculated to make so deep an impression on thoughtful 

 and educated readers as this volume. . . . The range and minuteness of the author's learning, the acuteness of 

 his reasoning, and the singular precision and clearness of his style, are qualities which very seldom have been 

 jointly exhibited in a scientific treatise." — N. Y. Sun. 



A Treatise on Chemistry. 



A Treatise on Chemistry. By H. E. Koscoe, F. R. S., and C. Schorlemmer, F. R. S., Professors of 

 Chemistry in the Victoria University, Owens College, Manchester. Volume III. — The Chemistry of the 

 Hydrocarbons and their Derivatives, or Organic Chemistry. Part I. 8vo, cloth. Price. $5.00. 

 Previous volumes are : Volume I.— Non-Metallic Elements. Price, $5-oo. Volume II.— Part I. — Metals. 

 Price, S3.00. Volume II.— Part II. — Metals. Price, $3.00. 

 " The authors are evidently bent on making their books the finest systematic treatise on modern chemistry 

 in the English language, an aim in which they are well seconded by their publishers, who spare neither pains nor 

 cost in illustrating and otherwise setting forth the work of these distinguished chemists." — London Athencpum. 



Adolph Strecker's Short Text Book of Organic Chemistry. 



Adolph Strecker's Short Text Book of Organic Chemistry. By Dr. Johannes Wislicenus. 



Translated and edited, with extensive additions, by W. H. Hodgkinson, Ph. D., and A. J. Greenaway. F. I. C. 



8vo, cloth, pages 790. Price, $5.00. 

 The great popularity which Professor Wislicenus's edition of " Strecker's Text-book of Organic Chemistry " 

 has enjoyed in Germany has led to the belief that an English translation will be acceptable. Since the publi- 

 cation of the book in Germany the knowledge of organic chemistry has increased, and that has necessitated many 

 additions and alterations on the part of the translators. 



D, APPLETQN & CO , Publishers, 1, 3 a nd 5 Bond Street, New York. 

 International Scientists' Directory. 



THE INTERNATIONAL SCIENTISTS' DIRECTORY for 

 1881-2, contains the names and addresses of from 15,000 to 20,000 

 Scientific men and amateurs in all parts of the world, together with 

 their special branches of Science, and other items of interest relating 

 to collections, duplicates, desiderata, etc. of each. 



Tnis is the first work of its kind ever attempted, and it will be 

 found of great value to all who are interested in any department of 

 Science. Price, in paper, $2.00. In cloth, $2.50. Sent post-paid 

 on receipt of price. S. E. CASSINO, Publisher, 



32 Hawley Street. Boston, Mass. 

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 The above are HICKEL PLATED and will be forwarded on receipt of $5.00. 



Address to Mr. MATHEWS, care of Office of "Science." 



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