THE AMERICAN CHEMIST. " 245. 



against one hundred and seventy in the fifties, of which ninety per- 

 tained to general inorganic chemistry, forty to organic chemistry, 

 twenty eight to methods of analysis and new forms of a-p])aratus for 

 analytical purposes, thirty to the analysis of minerals and mineral 

 waters; seven were on technical subjects, fourteen on meteorites, four 

 on agricultural chemical topics, and three on animal or vegetable phys- 

 iological chemistry. More attention was given in this decade than in 

 the preceding one to more purely scientific studies in general chemis- 

 try, for on inorganic and organi(; chemistry together there were one 

 hundred and thirty papers, against only sixty eight in the earlier jieriod, 

 while analyses of new minerals, also genuine scientific work, were 

 almost as numerous as before. The most prominent contributor was 

 Lea, nearly all of whose papers, over thirty in number, were on impor- 

 tant topics in both inorganic and organic chemistry. Cooke and Hors- 

 ford, of Harvard, and Gibbs and J. Lawrence Smith contributed 

 important papers, as did also Hunt; Warren made some important 

 contributions in organic chemistry. Other contributors were Brush, 

 Ordway, Crafts, and Wetherill. Hiiuichs first appeared with his theo- 

 retical essays, which some of us have perhaps attempted to master and 

 assimilate. Of the papers on general inorganic and organic chemistry, 

 about forty were from ten to thirty ]>ages in length, indicating, at least 

 as to quantity of nuiterial to be communicated, research studies of con- 

 siderable length. The proportion of such long papers was very much 

 snuiller in the preceding decades. 



There is nuich work deserving special mention in this decade, such 

 as Clark's "Constants of Nature," a collection of all the reliable deter- 

 minations of specific gravities, boiling points, melting points, specific 

 heats, and expansion by heat, an<l covering 450 octavo pages of the 

 ^SniWtsonian MlseellaneouH Collections; Warren's Monograph, of 100 

 quarto pages in The Transactions of the American Academy of Arts and 

 Sciences, ou "A new form of apiKiratus for fractional condensation of 

 volatile li({uids free from objections incident to the methods in use;" 

 and "Researches on volatile hydrocarbons; " also, his papers ou "A 

 new method for combustion in a current of oxygen gas alone, without 

 the use of cupric oxide;" and on "The analysis of organic substances 

 containing sulphur and chlorine." 



As one result of his work ou the hydro-carbons, Warren showed that 

 the elevation of the boiling point for an increment of CIT^ in homolo- 

 gous series is 30°, or much larger than was hitherto supposed; and 

 that in certain other series derived from the benzole series, differences 

 in boiling points for CII2 added or removed are much smaller than 19°, 

 Kopp's ligure. 



Worthy of mention is Lea's attempt at a classification of the elements 

 in several groups, the members of each group differing by 44-45, show- 

 ing that " the elements thus grouped consist of bodies whose proper- 

 ties are analogous — and that this classification is in harmony with the 



