14 



culture division of the Bureau of Entomology this laboratory is 

 investigating the chemical changes occurring during the storage of 

 honey and those produced by heating. 



Another line of work is the examination of samples of sugar corn, 

 grown in collaboration with the agricultural experiment stations and 

 the Bureau of Plant Industry, to determine the effect of environment 

 upon the sugar content. This work will be continued on other sugar- 

 containing plants. This laboratory also makes all analyses of sugar 

 beets sent to it by the Bureau of Plant Industry as a result of different 

 lines of experimental work. It also analyzes samples of sugar cane 

 grown in various sections of the country. In this connection, a 

 study is made of the methods of determining sugar in beets and cane 

 and other products of the sugar factory. An examination of beet 

 molasses from a large number of sugar factories is in progress. 



The laboratory collaborates with the International Commission 

 for Uniform Methods of Sugar Analysis in the preparation of pure 

 sucrose and the standardization of international quartz plates for the 

 control of polariscopes in different countries, the chemist in charge 

 being called upon to sit with this commission. 



In connection with the work of the various divisions and labora-^ 

 tories of this Bureau, the Sugar Laboratory makes many examina- 

 tions; the Contracts Laboratory referring to it all samples of dextrin, 

 glucose, starches, and other carbohydrate material received from 

 the Bureau of Engraving and Printing. 



As referee on sugar for the Association of Official Agricultural 

 Chemists, the chemist in charge cooperates in the study of methods 

 for the analysis of sugar, molasses, sirup, and other carbohydrates. 



NITROGEN SECTION. 



All nitrogen determinations for the several laboratories and divi- 

 sions are made in the nitrogen section in charge of Mr. T. C. Trescot. 

 Cooperative work with the Association of Official Agricultural Chem- 

 ists is also done looking to the improvement of the methods for mak- 

 ing these determinations. 

 - 



SPECIAL INVESTIGATIONS. 



From time to time various lines of investigation are undertaken by- 

 the Bureau which do not come strictly within the general scope of 

 any formally organized division or laboratory, and which require 

 special training. Such investigations are conducted by experts 

 reporting directly to the Chief of Bureau. The following lines of-j 

 work m&y be mentioned under this head : 



[Cir. 14] 



