268 Wells & Foote — One Hundred Years of Chemistry. 



A considerable amount of work with gases had been 

 done by Priestley, Scheele, Cavendish, Lavoisier, Dalton, 

 Gay-Lussac, and others before our hundred-year period 

 began. Cavendish, about 1780, had analyzed atmos- 

 pheric air with remarkable accuracy, and had even sep- 

 arated the argon from it and wondered what it was, and 

 later Gay-Lussac had shown great skill in the study of 

 gas reactions. During our period gas analysis has been 

 further developed by many chemists. Bunsen, in par- 

 ticular, brought the art to a high degree of perfection in 

 the course of a long period beginning about 1838, the last 

 edition of his "Methods of Gas Analysis'' having been 

 published in 1877. 



Important devices for the simplification of gas-analy- 

 sis in order that it might be used more conveniently for 

 technical purposes have been introduced by Orsat in 

 France and by Winkler, Hempel and Bunte in Germany. 



It appears that our countryman Morley has surpassed 

 all others in accurate work with gases in connection 

 with his determinations of the combining weights and 

 volumes of hydrogen and oxygen about the year 1891. 

 Some of his publications have appeared in the Journal 

 (30, 140, 1885; 41, 220, 1891; and others). 



Electrolytic analysis, involving the deposition of 

 metals, or sometimes of oxides, usually upon a platinum 

 electrode, was brought into use in 1865 by Wolcott Gibbs 

 through an article published in the Journal (39, 58, 1865). 

 He there described the electrolytic precipitation of cop- 

 per and of nickel by the methods still in use. The appli- 

 cation of the process has been extended to a number of 

 other metals, and it has been largely employed, particu- 

 larly in technical analyses. Important investigations 

 and excellent books on this subject have been the contri- 

 butions of Edgar F. Smith of the University of Pennsyl- 

 vania, and the useful improvement, the rotating cathode, 

 was devised by Gooch and described in the Journal (15, 

 320, 1903). 



General Inorganic Chemistry. 



The Chemical Symbols. — It is to Berzelius that we owe 

 our symbols for the atoms, derived usually from their 

 Latin names, such as C for carbon, Na for sodium, CI for 

 chlorine, Fe for iron. Ag for silver, and Au for gold. 

 We owe to him also the use of small figures to show the 



