RECliM WORK l.\ A(,Rll'i;i;ri:RAL SCIHNCE. 



AGRICULTURAL CHEMISTRY— AGROTECHNY. 



On some recent advances in our knowledge of the salts of proteins and of 

 their role in biological phenomena, T. P.. lioBERTSoN (/>'/>'• Austral, .l.s.sor. 

 A dr. Sei.. 11 {lUin). pit. 'I'JO-.'iOl ). — A dijii'st of data on the subject. 



Since, as the author jmints out. " proteins are ampholytes, and . . . cttnibino 

 with nonaniphoteric acids, bases, and probably salts, and we have seen that an 

 ampholyte system possesses tlie properties which have been ascribed to the ion- 

 proteids," he considers that the following assumptions are justitied: 



"The compounds which have been termed ' ion-proteids ' are in reality am- 

 pho-salts of the proteins (e. g., NaXOH, HXCl). 



" The nondissociable compounds of protein with non-ampboteric ions wliich 

 exist in tissues are in reality ampho-salts dissociating as acids and bases or 

 else di-salts (e. g., NaX++OH-, H++XC1- or NaXCl). 



'• Tlie influence of electrolytes ui)ou the properties and reactions of living 

 tissues may prol)ably be r<>t'(M'red in the main to alterations in tlie ratio of the 

 (basic anipholates) e. g., HX++OH~) to the acid ampholates (e. g., H++XOH~ 

 ;nid to the formation of nmplio-salts and di-salts." 



Hydrolysis of ox muscle, T. B. Osrorne and I). R. Jones {Amcr. .Jour. 

 I'fn/nHt}.. 2't {190'.)), ,Vo. ;7. pp. .J.}7'-.'///6'). — Tlie partition of nitrogen in beef 

 muscle, as determined l)y the modified Hausniann metliod, was nitrogen as 

 ammonia 0.89 per cent, as l)asic nitrogen 4.42 per cent, as noubasic nitrogen 

 10.44 per cent, and as nitrogen in magnesium oxid precipitate 0.43 per cent, 

 making a total of 16.1X per cent. 



"The nitrogen contained in tlie histidin, arginin, and lysin was equal to 4..">2 

 per cent of the dry muscle, which agrees vei"y closely with that precipitated by 

 phosphotungstic acid, thereby indicating the probable accuracy of the deter- 

 mination of these bases." 



Electrolytes and colloids. The physical state of g'luten, T. B. Wood and 

 W. B. Hardy (/Voc. Ron. Soc. \ London \. Her. B. SI (invH). No. B J.}.T. /*/). 

 38-.'t.h fif/s. 2; rtft-s-. in Jour. Chvm. .Sor. ^London}, 9(i {190!)), No. o.')9, I, p. 

 SJfl). — The gliadin of wheat is insoluble in distilled water and in acid over 

 certain critical concentrations. Dilute acid destroys tliis cohesion and forms 

 hydrosols, but salt solutions containing acid reestablish the coliesiveness. Alka- 

 lis act in a similar manner as the acids. 



The phenomenon is therefore in agreement with the hypothesis that gluten 

 hydrosol is a pseudo-solution caused by the existence of an electrical double 

 layer around the gluten particles. The hypothesis is supjiorted by measure- 

 ments of the potential differences between the 2 faces of the double layer by 

 means of the electrical conductivity of acid solutions of gluten and the rate of 

 transportation of the particles in a uniform electrical field. 



Colloid chemistry; an important branch of investigation for the agricul- 

 turist,'W. CzERMAK {Fiililinjf's Landir. Ztn.. .78 (1909). Ao. 17, pp. f;27-(!.n).- 

 A brief description of colloid chemistry and its probable relation to Mgiicult inc 



13042—0!) 2 *^^* 



