CYRUS MOORS WARREN. 397 



of organic compounds, for the estimation of sulphur and of chlorine, 

 and the determination of vapor densities. They contain among other 

 things a critical discussion of the methods of determining boiling-points, 

 and an exposition of the inaccurate methods and conclusions of some 

 of his predecessors. One of his conclusions was, " that the boiling- 

 point difference for the addition of C H 2 in homologous hydrocarbons 

 is generally 30° C, — which is a much larger difference than had been 

 commonly supposed." 



Among the details of these researches will be found a statement re- 

 lating to the separation of hydrocarbons from oil of cumin, which, 

 though nothing more than an incident touched upon solely for the 

 sake of elucidating the main line of the research, may well be cited as 

 an example of neatness, completeness, and elegance in chemical work. 

 Due account being taken of the very small amount of material at his 

 disposition, this particular analysis well illustrates Warren's accuracy 

 and his skill as a manipulator. 



It is a matter for lasting regret that Warren was unable to carry 

 out his plans for studying the large collection of pure volatile hydro- 

 carbons which he accumulated during this period, and which for 

 many years subsequently he kept in store. As an example of these 

 things may be mentioned an extremely volatile, elusive, liquid sulphur 

 compound from coal-tar, which he separated in a state of purity and 

 had partially studied. Indeed, his process for determining sulphur in 

 organic compounds was devised for the purpose of analyzing this sub- 

 stance. As it boiled freely at the temperature of melting ice, it had 

 to be condensed by means of freezing mixtures. It was evidently a 

 compound of considerable scientific interest. He called it provisionally 

 " alliole." It is said that by taking pains to free benzol completely 

 from this contamination, the commercial value of the benzol was 

 increased. The purified benzol suited the anilin-makers better than 

 the ordinary article. 



From Boston, Warren moved to Brookline, and established another 

 private laboratory there, which was for the time and for his purposes 

 remarkably complete in its equipment. He fully intended to continue 

 his scientific investigations, but so many adverse influences accumulated 

 that he was unable to carry out his plan. For one thing, he was ap- 

 pointed to the Professorship of Organic Chemistry at the Massachusetts 

 Institute of Technology., though he resigned the position after a year 

 or two because it consumed too much of his time. He was continu- 

 ally appealed to also by his business associates, who besought him 

 to help them in new enterprises, and to deliver them from difficulties, 



