AGRICULTURAL CnEMISTRY. 807 



Electrolytic determination of nitric acid, O. L. Shinn (Jour, Amer. Chcm. 

 Sue, 30 (J 'JOS), Xu. [), pp. 137S-13SI ; ab,s. in Science, n. ser., 28 (1908), No. 

 Ill, pp. 219, 220; Set. Abs., Sect. A—Phys., 10 {1908), No. 130, p. 608).— "It 

 w.is found that by koepinp; roppor in solution, either by the addition of copper 

 su]i)hate during rtHluctioii, (ir by retarding the speed at which the anode 

 rotates, the nitric acid is completely rtnluced to ammonia. This may be 

 determined either Ity distilling or by titrating excess of acid. Results are almost 

 theoretiiiil." 



The determination of phosphoric acid as phosphomolybdic acid, P. CiiRis- 

 TENSEN {Tids-skr. Landbr. Planteail, 15 (1908), No. 3, pp. Jf5Ji-466; Ztschr. 

 Aualyt. Chcm.. J,7 (1908), No. 9-10, pp. 529-6/,5; abs. in Chcm. Ztg., 32 (1908), 

 No. 93, Rcpert.. p. 599; Chem. Zentbl., 1908, II, No. 16, p. 1379; Jour. Chem. 

 Soc. [London], O'/ (1908), No. 552, II, p. 895). — A series of comparative testa 

 of the complete molybdic method with the so-called direct metluxl is reported. 

 In the direct method the phosphoric acid is i)recii)itated in nitric acid solution, 

 freed from silica, with ammonium molybdate, and the precii)itate ignited and 

 weighed, the phosphoric acid being calculated by multiplying the weight of 

 the residue after ignition by 0.0394. The relation of the results obtained by 

 the direct method to the theoretical amounts was as 100 to lOS. This relation 

 is closer than that obtained in case of the complete method, and in the author's 

 opinion indicates an accuracy which is sufficient for all practical purposes. 



Application of the gasometric method to the exact determination of urea, 

 A. KoNciiESK (Jour. I'lutnn. <t Cliitn.. 6. .scr., 28 (1!)0S), No. 10, pp. 'i'i'i--i52). — 

 A critii-al sunnnary and discussion of methods. 



A method for the determination of ammonia in barnyard manure, R. K. 

 Kblstensen (Tidn.skr. Lundbr. I'lanteavl, 15 (1908), No. 1, p. 2.'f; abs. in Chem. 

 Ztfl.. 32 (1908). No. 93, Repcrt., p. 599).— The method described is based upon 

 distillation with a saturated solution of sodium hydroxid in a stream of air. 



The volumetric-alkalimetric determination of alkaline earths in fertilizers 

 and soils, <). Foi;kstkk (Landic. \'ers. Stat., 69 (1908), No. J-.}, pp. 235-243; 

 (lbs. in Chem. Ztf/., 32 (1908), No. 91, Repcrt., p. 581 ; Chem. Zentbl, 1908, II, 

 No. 2Ji, pp. 189'i. 1895; Jour. Chem. Soe. [London], 9', (1908). No. 5.1'/. //. p. 

 1072). — The use *)f hydnuhloric acid for the titration of the basic substances 

 Is propostMl in place of sulphiu'ic acid conunonly recommended. The use of this 

 acid gives as a rule higher, and in the author's oi)inion, more accurate results. 

 'I'lie details of the i)roposed method of titration are given. 



Determination of the combined lime in humus, I', de Mondesib (Jour. Agr. 

 I'nit.. n. s(r., 16 ( I90.S), No. .'I'l. pp. 55'i-557). — This article discusses the impor- 

 tance of the lime conihinetl with htunus In soils and describes methods of 

 «leterminiiig what is termed the lime e<piivalent of soils. This determination 

 1» based upon the amoimt of calcium carbonate reduced when soils are treatc^l 

 with this snhstiinre. 



On the determination of carbon dioxid in water, I'. (Jmi {<lsn<llifs. lutjeu., 

 31 { r.iOS), No. ',7, pp. 7.i7-7.'i2). — Investigations on this subject are reviewed. 



Hydrolysis of vignin of the cowpea, T. B. t)sBORNE and F. W. Heyl (Amcr. 

 Jour. I'hi/siol., 22 (1908), No. 3, pp. 362-372).— The hydrolysis of vigniu of the 

 <'owpea ( \ iijnn .sinensi.'t), a globulin which is the principal protein present, 

 gave restjlts "similar to those found for the proteins of other leguminous 

 seeds, e. g., legumin, vicilln, phaseolin, and glycinin. .Mthough these proteins 

 are in many respects much alike, sutiiciently positive difl'erences. of one kind 

 or ai'other, exist ttetween them to leave no doubt that each is a distiuctly 

 diff« rent protein. 



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