210 EXPERIMENT STATION RECOED. 



a discussion in regard to the histology and microscopical analysis of the A^arious 

 vegetable feeds for animals which are sold in the form of cakes. 



Customs examination of rye and wheat brans, R. Woy {Ztschr. Offcntl. 

 Chem., 11 {1911), No. 6, pp. 101-109; a6s. in Chem. Zentbl, 1911, I, No. 19, p. 

 i////7; Analyst, 36 (1911), No. Jf24, p. 850).— Judging bran on the basis of its 

 ash content is considered irrational by the author, who also believes that the 

 more recent German official method, which takes into account the proportion 

 of bran which passes through a fine sieve, is not much better. He deems the 

 determination of the starch content the proper method for the valuation of 

 such materials. 



The author gives preference to the Ewers method (E. S. R., 21, p. 108). 

 Working "with 5 gm. substance, and polarizing in a 200 mm. tube at 20° C, 

 [he] finds the correct factor (assuming the use of the Soleil-Ventzke scale) to 

 be 1.892. It is suggested that some substance other than coal dust might be 

 prescribed for denaturing bran — some substance that would not detract so much 

 from its commercial value, whilst attaining the object of the customs au- 

 thorities." 



Errors in milk examination, H, Pflugradt (Molk. Ztg. [Hildesheim], 25 

 (1911), No. 11, pp. 183, 184)- — In this article the author discusses the reliability 

 of the Gerber acid butyrometric test, and calls attention to the necessity of hav- 

 ing properly graduated apparatus for doing the work. 



Refractometry of milk, C. Mai and S. Rothenfusser (Ztschr. Fleisch u. 

 Milchhyg., 21 (1911), No. 5, pp. 150, 151). — This is a discussion in regard to 

 certain statements of Riihm (E. S. R., 25, p. 207), in reference to the value of 

 the refraction of the calcium chlorid milk serum and the nitrate reaction for de- 

 tecting added water in market milk. The authors consider both of these tests 

 very reliable, and they do not agree with certain statements made in Rievel's 

 text-book (E. S. R., 19, p. 471). 



[Refractometry of milk], RiJHM (Ztschr. Fleisch u. Milchhyg., 21 (1911), 

 No. 5, pp. 151, 152). — This is a reply to Mai and Rothenfusser, in which the 

 author states that he does not deny the scientific value of the refractometric 

 method, but that it is not a practical one for the use of the veterinarian. 



Refractometry of milk, Rievel (Ztschr. Fleisch ti. Milchhyg., 21 (1911), No. 

 0, pp. 169-171). — This is a polemical article, in which the author points out 

 that he does not deny the practical utility of the calcium chlorid milk serum 

 refraction test, but is inclined to believe that the test can not be wholly relied 

 upon for detecting added water to milk and should be used only in conjunction 

 with other methods. In regard to the reliability of the nitrate reaction for de- 

 tecting watering, he can not attribute the value to this test which is given it by 

 Mai and Rothenfusser. 



A comparison between tlie refraction and the specific gravity of milk 

 serum for the detection of added water, S. Bull (Jour. Indus, and Engin. 

 Chem., 3 (1911), No. 1, pp. 4-'f--i6). — As a preliminary to this work the author 

 made a parallel determination of the refraction of the milk serum (acetic acid) 

 and the fat content (Babcock method) of milk. The results show that no re- 

 lation exists between the two, and that a milk serum from the same cow will 

 vary in refraction if taken at different times. The author expresses the opinion 

 that in view of this finding the method is not an accurate one for detecting 

 added water, unless the milk is known to come from a large herd. 



The other tests in regard to the refraction and specific gravity showed that 

 " the specific gravity of the serum is a much more delicate test for added water 

 than the refraction, but owing to the fact that all authorities are not agreed as 

 to the low limit of the specific gravity of pure milk serum, the author would say 

 that it is not as reliable in all cases as the refraction. Both methods combined 



