AGRICULTURAL CHEMISTRY. 209 



effected by formaldehyde, the amid-hydrogeu being replaced by the methylene 

 group. 



Pepsin and rennet, I. Bang (Ztschr. Physiol. Cheni., 5^ (1908), No. Jf, pp. 

 So9-36.2). — The author believes that these two substances are not identical. 



Methods of determining the moisture content of butter, G. L. McKay and 

 J. Bower {loira 8ta. Bui. 97, pp. .'i-39, figs. 8, dgin. 1). — A description is given 

 of several methods of determining the moisture content of butter, including the 

 official, Gi-ay, Richmond, Patrick, and Irish methods, the Wisconsin high-pres- 

 sure oven, the Carol! and Geldard testers, the Wagner butter hygrometer, and 

 a new method devised by the station and termed the Ames method. The various 

 methods are discussed with special reference to their use in creameries, their 

 simplicity, the cost of apparatus and of manipulation, and the intelligence of 

 operators being taken into account. Results obtained in tests of several -of the 

 methods are reported and compared with those from the ofBcial method. 



In the Ames method, which is designed to overcome inaccuracies involved in 

 the use of the aluminum beaker methods, due to lack of control of heating tem- 

 peratures, a 10 gm. sample is weighed into a tared aluminum beaker or other 

 suitable vessel which is then inserted in a vessel containing paraffin at from 150 

 to 200° C. until foaming ceases, shaking occasionally. The best results are ob- 

 tained at a temperature approaching 175°. After heating, the beaker is care- 

 fully wiped to remove any paraffin that may have adhered, cooled, and re- 

 weighed. If preferred, the beaker may be inserted in a slightly larger beaker 

 during the heating, tliereby eliminating any error through the adhesion of par- 

 affin. Of 50 analyses by this method 6 only varied 0.2 per cent from the official 

 method, and 1 only was in excess of 0.3 per cent difference. 



Directions for the selection and care of scales, sampling butter and preparing 

 the sample, with analyses showing the variation in water content of butter from 

 different parts of the churn, different tubs from the same churning and differ- 

 ent parts of the same tub, are given. 



German and American lard, E. Seitter {Ztschr. Uutcrsuch. JSahr. u. Genuss- 

 mtl., 15 (190S), No. 8, pp. -^85, //SC). — Characteristic differences in German and 

 American lard are discussed with a view to their differentiation in food analysis. 



Crystallization experiments with, lard and tallow, E. Seitter (Ztschr. 

 Vntersiich. Xalir. u. GcniissiiitL, LI (1908). Xo. 8, p. .'i86). — According to the 

 author, the addition of tallow to lard may be detected by characteristic differ- 

 ences in lard and tallow crystals. In the method' described a gram of the fat 

 was dissolved in 15 cc. of chloroform, 30 cc. of absolute alcohol was then 

 added, and the mixture allowed to stand over night in a stoppered flask at 

 medium temperature. The crystals formed were removed by filtration, washed 

 with absolute alcohol, and studied microscopically. 



Concerning that portion of meat extract which, can not be salted out, 

 K, MicKO (Ztschr. Uutcrsuch. Nahr. u. Gcnussmtl., 15 (1908), No. 8, pp. JfJt9- 

 -'i62). — In the portion of meat extract which can not be salted out the author 

 identified mouamino and diamino acids, the present report being taken up 

 with the first-mentioned group. This included glycocoll, alanin, leucin, aspartic 

 acid, and glutaminic acid, as well as taurin. He believes that alanin, glutaminic 

 acid, and taurin are original constituents of the meat extract. 



Extract of meat, C. M. AY. Grieb (Pharm. Jour. [Loiidon'], J,, sen, 26 (1908), 

 No. 1911, pp. Jf.'il, JfJfZ). — A note on analytical methods followed in the examina- 

 tion of meat extract for the detection of yeast extract. 



Methods for the analysis of vegetable foods, J. Alquier (Ann. Sci. Agron., 

 S. scr., 2 (1907), I. pp. .'i7-10.]). — A summary and discussion of methods used 

 for determining the composition of vegetable foods. 



59778— No. 3—08 2 



