Chemistry and Physics. 555 



The ionic equations are less satisfactory than molecular equations 

 in showing- the products of reactions, especially when the quan- 

 tities of the reacting substances are under consideration. The 

 extreme ionic view leaves out of consideration the large proportions 

 of un-ionized compounds that occur in ordinary solutions, as well 

 as the absence of ions in solids. The book carries out the ionic 

 idea to an extreme extent. For instance, it says in connection with 

 the removal of certain metals ("cations higher than group I") by 

 boiling the solution with sodium carbonate, "If ammonium ions are 

 present, the boiling should be continued until they are expelled." 

 Now, since it is ammonia and not the ammonium ion that is 

 expelled, it would appear better to mention it as such. The con- 

 tinual use of the word "ion " in the book seems to be unnecessary 

 and unsatisfactory. It would seem simpler and better to speak of 

 testing for phosphates instead of "the phosphate ion," for chlorides 

 instead of " the chloride ion," for potassium instead of " the 

 potassium ion," and so on, for it is not only superfluous, but it is 

 inconsistent to refer to the examination of solids for ions. 



h. l. w. 



4. Chemistry in America ; by Edgar F. Smith. 8vo, pp. 

 356. New York, 1914 (D. Appleton and Company). — Dr. Smith 

 has rendered an important service to chemists by the publication 

 of these " Chapters from the History of the Science in the United 

 States." The book deals extensively with the early history of 

 chemistry in Philadelphia, its important starting-point. There is 

 much of interest regarding Joseph Priestly after his arrival in 

 America ; concerning Joseph Hare, the inventor of the compound 

 blowpipe, and a celebrated investigator in other lines ; in con- 

 nection with the studies of the elder Benjamin Sillimau at that 

 city ; and about many other interesting chemists. The book 

 contains excellent portraits of Robert Hare, James Woodhouse, 

 Joseph Priestly, Thomas Cooper, John Maclean, Samuel Latham 

 Mitchell, Benjamin Silliman, James C. Booth, T. Sterry Hunt, J. 

 Lawrence Smith, Wolcott Gibbs, M. Carey Lea, Josiah Parsons 

 Cooke and J. Willard Gibbs. This list of portraits shows the 

 scope of the book, although the work of many others is men- 

 tioned, usually briefly. No attempt has been made to discuss the 

 chemical work of recent years. h. l, w. 



5. Annual Reports of the Progress of Chemistry for 1913. 

 Volume X. Issued by the Chemical Society. 8vo, pp. 300. 

 London, 1914 (Gurney & Jackson, 33, Paternoster Row, E. C). — 

 These reports on the different branches of chemistry are particu- 

 larly suitable for enabling specialists in one branch of the science 

 to learn the main features of progress in the other branches. The 

 reports are short and condensed, they have been prepared by 

 prominent scientists, and include the following titles : General 

 and Physical Chemistry, Inorganic Chemistry, Organic Chemis- 

 try, Part I, Aliphatic Division, Part II, Homocyclic Division, 

 Part III, Heterocyclic Division and Stereochemistry, Anatytical 

 Chemistry, Physiological Chemistry, Agricultural Chemistry and 



