be labeled to suit the instructor's inclinations, the in- give each sample a serial number. At the time this is dividual samples must be designated in such a manner done there is entered a t the corresponding number in as not to reveal anything to students, some of whom a record book the stock number of the sample. In show their greatest originality when trying to work out checking an analysis one must first consult the book the instructor's system of samples. Although it in- of serial numbers to determine the stock number. The volves more work than some "key" systems, in the latter, together with the analyses, are kept in a sepa- authors' experience the only fool-proof practice is to rate book.

LANGMUIR AWARD

THE American Chemical Society Award in Pure Chemistry was established in the spring of 1931 a t the suggestion of Dr. Arthur C. Langmuir, who generously assumed the financial burden of the award for the first few years. Designed to encourage and recognize out- standing chemical research in pure science, the award is to be made a t the fall meeting to a person preferably less than thirty years of age and of American univer- sity or college connection. The award is one thousand dollars.

PRESIDENT CHARLES L REESE 01 THE AMERICAN CAEMI- CAL SOCIRTY PRESENTING THE LANGMUIR AWARD POR 1934

TO DR. C. FREDERICK KOELSCH

C. Frederick Koelsch is the 1934 recipient of the Langmuir Award for outstanding work in the field of organic chemistry. With Professor S. M. McElvain, he investigated the reaction between epichlorohydrin

and various Grignard reagents, and studied the prepa- ration of thioglyceric acids. While he was still a t the University of Wisconsin, he devised his method of identifying phenols using chloroacetic acid as a reagent to form the readily manipulated aryloxyacetic acids. This method is in wide use at the present time. Here, too, was initiated the first of a series of researches upon the chemistry of highly phenylated compounds with the study of the reactivity of the halogen in ben- zoyldiphenylmethyl bromide.

While a t the University of Illinois and as National Research Fellow in Chemistry at Harvard University, he prepared a new type of Grignard reagent, triphenyl- vinyl magnesium bromide, and investigated its "nor- mal" and "abnormal" reactions. This led to the study of the pentaarylallyl alcohols and the closely related tetraarylindenes, formed by ring closure. In this con- nection, he succeeded in synthesizing a molecule hav- ing two fused five-membered rings adjacent to each other on a benzene ring, I-diphenylene-2-phenyl-3,4- phenyleneindene. This type of ring structure up to that time was considered to be incapable of existence. Geometrical isomers were isolated in the triarylvinyl halide series, due to asymmetry about the ethylene linkage. Cis and trans structures were assigned based on the products obtained by ring closure bf the acids to diajlindones.

C. Frederick Koelsch. and his students. continued -

this type of research a t the University of Minnesota. Triphenylvinyl mercaptan was prepared and found to show all the reactions of mercaptan, as contrasted with the oxygen analog, diphenylacetophenone, which reacts as the ketone. This study in keto-en01 isomer- ism is one bit of evidence indicating the reluctance of sulfur to form a double bond with carbon as oxygen readily does. The polymerizability of thioketones and their general reactivity and high color also show this. An improved method of identifying the acyl group in esters as the acid toluidides was devised. Later Koelsch synthesized 2,3-benzofluorene, and studied the products obtained by dehydration of tetra- arylallyl alcohols, and the action of sodium upon phenylphe&nthrene ether. These studies, as in the case of his earlier ones, tend to define and make clear the theoretical basis of organic chemistry.-Isotopics