REPORT OF THE CHEMIST. 



United States Department of Agriculture, 



Bureau of Chemistry, 

 Washington, D. C, October 13, 1917. 

 Sir: I submit herewith the report of the work of the Bureau of 

 Chemistry for the fiscal year ended June 30, 1917. 

 Respectfully, 



C. L. Alsberg, Chief. 

 Hon. D. F. Houston, 



Secretary of Agriculture. 



The research of the year has yielded some interesting results, such 

 as the discover}' of a new sugar, sedoheptose, from Sedum spectahile, 

 of a new method for the preparation of phthalic anhydride, of new 

 sugar derivatives, of new facts concerning the proteins of agricultur- 

 ally important seeds, concerning the arsenates and chlorarsenates of 

 lead, and concerning the explosibility of carbonaceous dusts. Other 

 important results deal with the identification of the volatile reduc- 

 ing substances of vinegar as acetylmethylcarbinol ; the improvement 

 of the methods for the separation of lithium from the other alkali 

 metals, and for the identification of lactic and butyric acids in 

 biological products. The results of about 60 investigations have 

 been reported and some 50 others completed. Nine bulletins and two 

 Farmers' Bulletins were published. 



More attention has been paid than ever before to the study and 

 demonstration of methods of conserving and preparing foodstuffs 

 by drying, canning, pickling, preserving, and by the use of meri- 

 torious substitutes. In consequence, educational and demonstration 

 work has grown very much during the year. 



The enforcement of the Food and Drugs Act has undergone no 

 radical changes. The disposition of the foodstuff' and drug indus- 

 tries to cooperate with the Bureau of Chemistry continues to grow 

 with a resulting improvement of the quality of their products and 

 the elimination of spoilage and wastes. While the number of cases 

 sent to prosecution is about the same as in former years, the amount 

 of work involved in perfecting a case is becoming steadily greater, a 

 certain indication of a very general improvement in commercial 

 practice. The progress of the past 10 years has been so great that 

 an effort has been made at the end of this report to summarize the 

 effects of the enforcement of the Food and Drugs Act during the first 

 decade since its enactment. 



RESEARCH. 



Plant chemistry. — Studies upon the effect of fertilizing wheat with 

 nitrates and potash at different states of growth have demonstrated 

 that nitrates applied when the wheat is beginning to head affect the 



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