DIVISION OF CHEMISTRY. 103 



discovered attempts are at once made to ascertain the cause of such 

 discrepancy and to devise means for obviating it. The result of this 

 collaborative work is that the various chemists in the appraisers' 

 laboratories are working more and more upon a uniform plan and 

 securing by far more uniform classifications than have ever heretofore 

 been obtained. 



WAR AND NAVY DEPARTMENTS. 



During the year large numbers of samples of foods and supplies for 

 the Army and Navy have been examined in the Division of Chemistry 

 upon request addressed to the Secretary of Agriculture. Most of these 

 examinations have been for food supplies, but many of them have 

 been for clothing and other things necessary to the Army and Navy at 

 home and in the Tropics. 



It seems desirable that there should be some central laboratory of 

 this kind where the various Departments of the Government can 

 secure chemical services, and the equipment and scope of the work of 

 the Bureau of Chemistry seems to indicate that it is here that such 

 work will be principally done. This is the more probable on account 

 of the hearty sympathy of the Secretary of Agriculture with the other 

 Departments in their efforts to secure a proper chemical control of the 

 foods and supplies which are demanded for the public service. 



POST-OFFICE DEPARTMENT. 



A number of investigations was made during the year for the Post- 

 Office Department with reference to the composition of articles which 

 it was desired to have forwarded through the mails and in the study 

 of problems submitted by the Postmaster- General relating to the 

 needs of his service. Among these may be mentioned the examina- 

 tion of inks, used not only in the service of the Post-Office Depart- 

 ment, but by the Department of State and many other Departments 

 of the Government. It is important that these inks should be plain, 

 legible, and, so far as possible, indelible. Large numbers of such 

 inks have been submitted to us by the Post-Office and State Depart- 

 ments. Their composition has been studied, the character of the 

 imprints they made ascertained, and reports made in regard to com- 

 parative efficiency to the various Departments requiring our aid. 



INTERIOR DEPARTMENT. 



The Division of Chemistry continued its cooperation with the 

 Interior Department in regard to the study of the composition of all 

 the important springs on the Government reservation at Hot Springs, 

 Ark. This work employed one of the chemists of the Division for 

 the greater part of the fiscal year, and the salary and traveling 

 expenses of this chemist were paid by the Department of the Interior. 

 The general details of the results of the investigation have been 

 reported from time to time through the Secretary of Agriculture, and 

 it is believed that a full report on this investigation will be ready to 

 go forward not later than the first of November. 



COLLABORATIVE WORK WITH THE ASSOCIATION OF OFFICIAL 

 AGRICULTURAL CHEMISTS. 



The cooperative work with the Association of Official Agricultural 

 Chemists has been prosecuted during the year as usual. All the 



