LETTER OF TRANSMITTAL FOR ORIGINAL EDITION. 



U. S. DEPARTMENT OF AGRICULTURE, 



BUREAU OF CHEMISTRY, 

 Washington, D. C., July 15, 1907. 



SIR: In view of the increasing importance, legally as well as 

 scientifically, of the methods of the Association of Official Agricul- 

 tural Chemists, in connection with the administration of the food and 

 drugs act, June 30, 1906, these methods being also those used in the 

 Bureau of Chemistry, it seemed of fundamental importance that they, 

 should be revised to date, no revision having been issued since 1S99, ; 

 with the exception of the record made in additional circulars and in 

 Bulletin 65 on food analysis, of the additions to and changes in the 

 methods. 



The difficulties of making such a revision, when the methods, espe- 

 cially those relating to foods, are continually the subject of study and 

 amendment, are apparent. Nevertheless it is believed that the pres- 

 ent revision, including all authorized changes and additions, the 

 rearrangement and consolidation of general and special methods, 

 and the elimination of repetitions or contradictory material, will so 

 add to the efficiency and usefulness of the methods as to warrant its 

 publication, although many other changes might be suggested. 



The revision is the work of the following committee, appointed by 

 the president of the association, previous to the meeting of 1906, 

 and provisionally adopted at that time: J. K. Haywood, chairman; 

 J. P. Street, F. W. Woll, J. H. Pettit, L. M. Tolman, F. P. Veitch, 

 and A. L. Winton. The preliminary work on the revision was done 

 by members of the Bureau of Chemistry. 



It is respectfully recommended that this manuscript be issued as 

 Bulletin 107 of the Bureau of Chemistry, superseding Bulletins 46 

 and 65, the revision to be in this form submitted to the association 

 for final approval at the meeting of 1907. 

 Respectfully, 



H. W. WILEY, 

 Secretary, Association of Official Agricultural 



Chemists; Chief, Bureau of Chemistry. 

 Hon. JAMES WILSON, 



Secretary of Agriculture. 



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