BUREAU OF CHEMISTRY. 139 



An important part of the work of the food Laboratory during the 

 last fiscal year was that done at the request of other Departments. 

 This includes samples from the subsistence departments of the Army 

 and Navy and nonalcoholic beers from the Attorney-General and 

 sheriffs in the Indian Territory. At the request of the Treasury 

 Department an investigation was also made of pineapples, in order to 

 determine as nearly as possible the amount of sugar that is added to 

 the canned pines imported into the United States from the Bahamas 

 and the Straits Settlements. To determine this a large number of 

 imported canned pines were obtained, and also ripe pines, from as 

 many localities as possible, including Florida, Cuba, Porto Rico, and 

 the Bahamas. Arrangements have also been made to have samples 

 of pines taken at Singapore preserved according to directions and 

 shipped to the laboratory for examination. 



The food laboratory has done an important work during the last 

 fiscal year in collecting, investigating, and comparing methods for the 

 examination of a large variety of foods. This work was taken up at 

 the request of the Association of Official Agricultural Chemists, in 

 which the chief of the food laboratory is at present the referee on food 

 adulteration. He has worked in cooperation with 13 prominent food 

 chemists of the United States and Canada in the preparation and col- 

 lection of these methods. The results of their labor have been pub- 

 lished as Bulletin Go of the Bureau of Chemistry, which forms a better 

 laboratory manual for the examination of the subjects it includes than 

 any single reference book that has been published. Since this bulle- 

 tin waspublished, three additional subjects have been treated by the 

 chemists to whom they were assigned. 



ROAD MATERIAL LABORATORY. 



This laboratory, of which Mr. L. W. Page was made chief, was 

 established in collaboration with the Office of Public Road Inquiries, 

 and is not yet fully equipped. The installation of the laboratory 

 began in December, 1900, and it was impracticable to begin work for 

 several months, on account of the time necessary for even a partial 

 equipment. Therefore the fiscal year ended June 30 last is the first 

 year of operation of this laboratory. 



The object of the road material laboratory is to obtain results, by 

 means of physical and chemical tests, from small samples of road 

 materials, to aid the road builder in selecting the most suitable mate- 

 rial available, and to advise him as to the best methods of construction 

 to be used in his work. 



Up to the present time it has been possible to test only materials 

 used for macadam, gravel, and clay roads. To properly meet the 

 various conditions of traffic and climate to which roads are subjected 

 with suitable road materials, it is necessarj' to carefully study the 

 chemical and physical properties of these materials, and it is here that 

 the principal work of the road material laboratory lies. In a broad 

 sense, the value of any road material is dependent upon the degree to 

 which it possesses certain phj'siealand chemical properties, and these 

 properties often depend on a peculiar chemical composition. The 

 work of the laboratory therefore comes under three principal heads, 

 viz, physical tests, for determining the degi*ee to which a material 

 possesses the essential physical properties necessary for good roads; 

 chemical analyses, together with the chemical investigation of certain 

 essential properties; and petrographic determinations of the various 



