AGRICULTURAL CHEMISTRY. 609 



iV.xtC,), \<i. ). /i/i. .V;7-.1S',). — This article reports a number of studies of factors 

 doteruiiiiin.t,' the accuracy of this method, especially the solubility of the alkalis 

 of the glass apparatus and loss of ammonia. With Jena glass apparatus there 

 was no considerable eiTor due to solubility of alkalis of the gla.ss. By use of 

 jirojicr prc<-,iiit idiis llie loss of anunonin need not be considerable, although it 

 can not be entirely prevented in distillation without cooling. In general, how- 

 ever, the method of distillation witliont a cojidenser ga\-e sui)stantially the 

 same I'csults as in casi' of the use of a condenser. 



The determination of ammonia in water by Nessler's reagent, A. P.uissoN 

 (Coiiiiil. h'cinl. Acad. Sci. \ I', iris]. / ',.1 (IH06), Ao. 5, p/). .>S<)-i'.)t; ubx. in Bill. 

 Sor. Cliiiii. /'(iris. .!. .■<(r.. .1.1 ( IDiii;). A o. ,?//. /). 13.i0). — According to the author's 

 iii\'<>sli,:,'atioiis llio prcci|iil,-i1c obtained with Xcsslcr's solution in wcMk solu- 

 tions of .ininioui.i (fi mg. per liter) has the following fornuila : llg„\,I,., a bi-o\vn 

 amorp!ion> iiody insolulde in neutral solvents, but soluble in potassium iodid, 

 which ill excess liberates all the nitrogen in tlie form of ammonia as follows: 

 lIg,X,I.,+ 1-KI + l-II/)-=!> lIgI,+4Xir,+ ll.'K()lI. All of the ammonia is not 

 precipitated, the jiroportiou being determined by varicms conditions of tem- 

 l>erature, dilution, preparation of reagents, etc. In the authoi-'s experiments 

 as much as 21 ]>er cent of the ammonia escaped ]irecipit;itioii. 



The Volhard method for the determination of chlorin in potable waters, 

 F. T. Shutt and II. W. Charlton {Tran.s. lion. ^'>c. Canada, 2. scr., 11 

 (1905-6), *s'cc. IJl, PI). 67-71; abs. in Chcni. Acfcs, i)', {11W6), No. 2J,o3, pp. 

 2-'>S-26()). — Comparisons of the Volhard and chromate methods on a large nuni- 

 b(>r of samples of w;iter are reported, the results showing that the Volhard 

 iiietliod while less rapid than the chromate is more satisfactory for waters 

 containing very small amounts of chlorin. 



Table of the principal physical and chemical constants of fats, I). 

 SiDKRSKY {1)1(1 11.^. Ijiiit. \l'ii)-ifi], 31 {I'.UH)), No. JfS, pp. 775, 776). — Constants for 

 2S fats and oils of .iiiiiii.il and vegetable origin calculated from compiled data 

 are reported in tabular ft)rm. 



A new method for the determination of casein in cheese, A. Trillat and 

 Saito.n (I'.iil. Sue. Cltiiii. I'uiis. 3. .sr;-.. 3.')-36 {l'.H)6), No. 23, pp. 1207-1210).— 

 This is a direi-t method for the determination of casein in cheese, based upon 

 the same principle as the method tor the determination of casein in milk pre- 

 viously noted (E. S. K., IS. p. '.)). 'J'lie method is believed to show accurately 

 the amount of proteids in cheese which have not undergone transformation 

 during the process of ripening. 



In applying the method to commercial samjiles, the following percentages of 

 casein were obtained: Camembert, 1S.20; Gruyere, 31.34; Gervais, (5.42; Brie. 

 22.93; Roquefort (half ripened), 11.(;.5: Ptoquefort (well ripened), 7.10; and 

 Holland, :•. !..-.( I. 



The classification of animal and vegetable proteids in relation to their 

 products of decomposition, J. II. Mill.vr ('J')-(iii.s. G)(i)iii<.s.s Uisain-li Lab.. 1 

 ( r.XKJ), pt. 2, pp. l.'i!)-166). — A summary and discussion of data with a view to 

 classification of proteids. 



Concerning glutamins, E. Schulze (fjandir. ^'r^•.'^. Htaf.. 65 {1006), No. 

 3-.'i. pp. 2.37-2.'i6). — The author notes that there is considerable variation in the 

 reported measurements of the o](tical activity of glutamin. A number of such 

 measurements made with glutamins of known origin are reported and compared 

 with the author's earli(>r work and with that of other investigators. In his 

 opinion, it is not improbable that the variations are due to the existence of 

 glutamins in stereolsometric forms. 



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