AGRICULTURAL APrilOPRlATION BIU^ 1924. 255 



(tr to tlu» extent to whicli there was fniuil involved in the therupi>uti(- 

 chiiins nuuh' for certain pre[)iirationH und, therefore, the I^wt OHice 

 Department has caUed M|)on the liineau of CheniiHtrv for uMHiNtanee 

 in this work. We have appreeinted that it was an iin<h"rtaking 

 synipatht'tic with the purposi's of tlie food and drw^ act itself and we 

 have us<'d the hi^jjest portion of this fiiiul for that. 



INVESTIGATIONS OF K.\W M.VTKKI.VLS KOK ('OI.(>ltlN«i . IK. 



'I'he next item is for tlip investijjation and experiment in the 

 utih/ation for (•t>h)rin«;. medicinal and technical purposes, of raw- 

 materials jjrown or produced in tin* liiited States. This is the fund 

 that supports the work of the color lahoratorv. This af)propriation 

 was asked at a time when the department or bureau undertook to 

 assist the color manufacturinj:^ industry in this <-ountrv hy a deter- 

 mination of methoils by which it would not only utilize the inter- 

 mediates available but could, in fact, manufacture them and not 

 be dej^endent upon forei«j:n soun-es for that supply. 



That work has chanrjed in its character very materially since then. 

 You know that some of the work of the laboratory has elfected 

 tremendous economy in the manufacture of some of these color 

 products or the basic material from which they are made, such as 

 phthalic anhydride, and its attention, instead oif being given now so 

 much to the cjuestion of tonnage production, as was the case origi- 

 nally, is bein^ directed to some special phases of color work which 

 the industry itself is not taking up. One of the ti^reatest difficulties 

 confronting the industry in color manufacture is some means by 

 which there can be a definite and correct identification made of 

 colors. It is essential to make that study from the standpoint of 

 art and the value of those colors for dyeing purposes. We have been 

 working in the past year upon methods ot identification by which, 

 upon proper analysis, definite colors could be identified and the 

 extent of the impurities made known. 



IN'VESTIOATION FOR A STABLE BIOLOGICAL 9TAIS. 



In addition to that we have also been giving particular attention 

 to a concern which has been manifesting itself on the part of the 

 scientific w^orld, and that is for a stable biological stain. This bio- 

 logical stain is used by bacteriologists, pathologists, physicians, and 

 veterinarians in staining, studying and identifying disease-producing 

 or^janisms. 



That particular stain was derived exclusively from Germany 

 before the war. The firm that manufactured that stain went out 

 of business as a result of tiie war, and, as a matter of fact, it is ni)t 

 being manufactured at all now. It is no longer available, and because 

 of the fact that it is not a tonnage proposition, it is a question that 

 does not in itself appeal to color manufacturers. But the replace- 

 ment of that particular stain or the tleterniination of some other 

 stain that will answer the purpose is of the utmost importance to the 

 scientific world. The Bureau of Chemistry, in cooperation with 

 scientific agencies that are undertaking to test out the fabricated 

 dyes for this purpose, is now trying to determine some stain that 

 will answer that particular service. 



22028—22 17 



