BUREAU OF CHEMISTRY. 467 



adulteration by the chemical analysis. Bacteriological determina- 

 tions are not included in this statement. Of the 239 hearings re- 

 ported, about 100 were conducted by correspondence. The chief of 

 the laboratory was detailed during the year to certain large eastern 

 cities to assist in milk campaigns such as had been conducted at 

 Cincinnati. 



DENVER LABORATORY. 



The percentage of the 570 interstate samples examined that were 

 found to violate the law was about 31, a slight but not significant de- 

 crease as compared with last year. The violations by shortage of 

 weight or measure, which last year predominated, showed a decided 

 diminution, and in most instances were due to lack of uniformity in 

 the size of the containers rather than to any fault of the manufacturer. 

 The form of illegality most frequently found consisted of exaggerated 

 and misleading statements on the labels. 



Research work has been continued on lemon extracts and oils, com- 

 paring various methods for the determination of citral in these sub- 

 stances. In connection with this work the possibility of determining 

 citronellal in lemon oils has also been studied, using both fuchsin 

 sulphurous acid and metaphenelene diaminhj^drochlorid. 



A simple and reliable method has been elaborated for making quick 

 ether extract determinations on dry powdered substances, such as 

 cocoa, coffee, spices, etc. Its usefulness lies in the amount of time 

 saved, the process of extraction consuming only a few minutes for 

 each sample as compared with twenty hours by the official method^ 

 and the results so far obtained by the two methods agree remarkably 

 well. It is not intended that the proposed method should be substi- 

 tuted for the official one, but it offers a simple and rapid means by 

 which the analyst may separate the genuine from the adulterated 

 samples. 



Forty-four samples were examined for the Treasur}' and "War de- 

 partments, consisting of a few samples of drugs for the Customs 

 Service and a considerable number of spices, etc., for the commissary,, 

 Department of the Colorado, cooperative work on methods for the 

 examination of sugars and flavoring extracts and on maple products 

 and the detection of capsicum, etc., in ginger ales. 



Nearly all of the IGO hearings held b}'^ the Denver laboratory dur- 

 ing the year were conducted by correspondence. The torritor}- from 

 which samples are commonly purchased and sent to the Denver lab- 

 oratory for analysis comprises Colorado, Utah, Wyoming, part of 

 Nebraska, western Kansas, New Mexico, Arizona, and Nevada, a very 

 large but rather sparsely populated area. Again, Denver is not in 

 itself an extensive or important producer of foods as compared with 

 eastern cities, but is a comparatively large distributor of foods 

 through a district covering a considerable portion of the States 

 named. These conditions materially affect the character of the hear- 

 ings, the results being that few manufacturers are cited on samples 

 examined in the Denver laboratory. 



DETROIT LABORATORY. 



• 



The work of the Detroit laboratory, as in previous years, has con- 

 sisted principally in examinations of domestic samples. Of the 295 

 interstate samples about 50 per cent were found to be illegal. Notice- 



