280 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE. 



show that poisoning of this character might readily occur if left-over 

 foods were kept at room temperature in pantries, storerooms, or other 

 places sufficiently warm to permit the growth of the organism, but 

 that in the temperature of a properly kept ice refrigerator foodstuffs, 

 even though contaminated, would not become dangerous within a 

 period of two or three days. This work is being prepared for publi- 

 cation. 



MICROCHEMICAL INVESTIGATIONS. 



The microchemical laboratory makes examinations and studies of 

 food and other products involving the use of the microscope. It 

 investigated during the year methods of grading, sampling, and 

 examining nuts. A large number of import samples of canned and 

 dried mushrooms have been examined for insect infestation. Studies 

 were conducted upon decomposition in fruits with a view to arriving 

 at criteria for judgment of this class of products under the food and 

 drugs act. These studies included blackberries, raspberries, logan- 

 berries, peaches, and apple products. As a result of this work the 

 bureau is in a better position to judge such products than ever before. 



Studies made uj^on flour with a vieAv to grading the product by 

 microscopical means have been further extended during the past 

 season and a modified microscopical method for examination has 

 been devised which simplifies considerably the method as originally 

 worked out and published. 



Further studies upon methods of estimating the shell content in 

 cocoa and chocolate products have been made and a method tenta- 

 tively adopted. 



Regulatory work in the examination of samples and the review 

 and preparation of evidence in cases was continued during the year 

 and involved principally the following food products : Tomatoes, 

 cocoa and chocolate, egg substitutes, nuts, canned fruits, stock feeds, 

 and jams and jellies. 



CONTROL OF STOCK FEEDS. 



The cattle food and grain investigation laboratory performs the 

 services of a staff laboratory in applying the food and drugs act to 

 stock feeds and grains. All cases involving these products are re- 

 viewed and recommendations made. Information regarding stock 

 feed and grains is furnislied the inspection districts to guide them 

 in applying the law to adulterated and misbranded products. Work 

 was done to determine standards and definitions for various cattle 

 feeds, and to unify the methods of analysis used in the various 

 laboratories of the bureau. 



CONTROL OF BEVERAGES. 



The water and beverage laboratory acts as a staff laboratory in the 

 control of water, beverages, flavors, and related products. In co- 

 operation with the stations of the eastern district, a sanitary survey 

 was made of mineral springs located in Virginia, West Virginia, 

 North Carolina, South Carolina, and Georgia. A paper on "Radio- 

 activity of miscellaneous waters examined in the Bureau of Chem- 



