Wolcott Gills. 255 



appeared the account of his great investigation of the ammonia- 

 cobalt compounds with F. A. Genth, which contained so full 

 and thorough a study of the principal series of these puzzling 

 bodies that very little in the way of experiment was left for 

 future work, the analytical and chemical work being supple- 

 mented in many cases by crystallographic determinations by 

 J. D. Dana. So exhaustive a research was a new thing in 

 American chemistry, and at once established his reputation on 

 a firm basis. 



In 1861 appeared the first of three papers on new methods 

 of separating the platinum metals, an important research on a 

 most difficult subject, which was a worthy companion of his 

 great work on the ammonia-cobalt compounds. These investi- 

 gations led to his election in 1863 to the Kumford Professor- 

 ship of the Application of Science to the Useful Arts in 

 Harvard University, left vacant by the retirement of Professor 

 E. 2sT. Horsford, and accordingly, after he had established 

 himself in Cambridge, he took charge of the chemical labora- 

 tory of the Lawrence Scientific School. The number of his 

 students was small, but more were not to be expected or 

 desired, as the object of the course was to educate professional 

 chemists, and the supply was somewhat greater than the 

 demand. His own work during this period is described in a 

 number of short papers principally on chemical analysis ; the 

 most conspicuous of which, introducing the electrical deposi- 

 tion of the metals as a means of their quantitative determina- 

 tion, laid the foundation of what has since become a new 

 department of the science — electrical analysis. Another of 

 these papers on the sand or glass filter is interesting as a fore- 

 runner of the Gooch crucible, and his experimental method for 

 correcting the volumes of gases may also be mentioned. 



In 1871 a reorganization of the Chemical Department con- 

 solidated the laboratory of the Lawrence Scientific School with 

 that of Harvard College, and relegated Dr. Gibbs to the 

 Department of Physics, where he taught a small advanced 

 class in Light and Heat. Some papers on optical subjects 

 inspired by the discovery of the spectroscope probably led to 

 this assignment, which was justified on the score of economy, 

 but its wisdom may be doubted, as it deprived the chemical 



