1919] AGKICXJLTURAL, CHEMISTRY AGROTECHNY. 11 



Lysin as a hydrolytic product of hordein, C. O. Johns and A. J. Finks 

 {Jour. Biol. Chem., S8 (1919), No. 1, pp. 63-^6).— Analyses of hordein by the 

 Van Slyke method are i-eported from the Bureau of Chemistry, U. S. Depart- 

 ment of Agriculture. The average distribution of nitrogen corrected for solu- 

 bility of bases was as follows: Amid N 23.85 per cent, humin N absorbed by 

 lime 0.84, humin N in amyl alcohol extract 0.28, cystin N 0.81, arginin N 5.37, 

 histidin N 3.63, lysin N 1.01, amino N of filtrate 49.35, and nonamino N of fil- 

 trate 14.20 per cent. The basic amino acids in percentage of total protein were 

 cystin 1.18, arginin 2.82, histidin 2.27, and lysin 0.89. These results agree quite 

 clo.sely with those obtained by Osborne et al. on gliadin (B. S. R., 33, p. 867), 

 but differ considerably from the earlier analyses of hordein reported by Os- 

 borne and Clapp (E. S. R., 19, p. 611) and Kleinschmitt (E. S. R., 20, p. 907), 

 who isolated the basic amino acids by the direct method of Kossel and found no 

 evidence that hordein contained lysin. 



Comparative tests of palau and rhotanium ware as substitutes for plati- 

 num laboratory utensils, L. J. Gurevich and E. Wichers {Jour. Indus, and 

 Engin. Chem., 11 (1919), No. 6, pp. 570-573). — A detailed report is given of a 

 series of tests conducted at the Bureau of Standards, U. S. Department of Com- 

 merce, to determine the suitability of "palau" and "rhotanium" (alloys of 

 gold and palladium) as substitutes for platinum in laboratory ware. 



" These tests indicate that rhotanium A ware is superior to platinum ware 

 both of high (2.4 per cent) and low (0.6 per cent) iridium content in respect to 

 its resistance to loss on heating. The losses on treatment with acid, after heat- 

 ing, are about equal. Grade A ware compares favorably with platinum in re- 

 sistance to boiling hydrochloric acid, to boiling 20 per cent sodium hydroxid, 

 and to fusion with sodium carbonate in a muffle, and with potassium pyrosul- 

 phate. It is superior to platinum in resistance to the action of boiling sulphuric 

 acid, and inferior in its resistance toward boiling concentrated and dilute nitric 

 acid, boiling 10 per cent ferric chlorid solution, and for fusions with sodium 

 hydroxid. The only objection that may be raised to its use is the rather low 

 melting point of the alloy, which makes it Impossible to blast or strongly heat 

 the ware without melting it. 



"As far as resistance to loss in weight on heating to 1,200° C. is concerned, 

 rhotanium C and palau wares are about equal, if not slightly superior, to plati- 

 num ware containing 0.6 per cent iridium. . . . Palau and rhotanium C behave 

 toward reagents in about the same way as rhotanium A, except that they are 

 not suitable for potassium pyrosulphate fusions and are inferior to grade A 

 for sodium hydroxid fusions. . . . 



" Palau and both grades of rhotanium may all be used to advantage in the 

 electrolysis of chemical solutions, but only as cathodes. As anodes the alloys 

 are worthless." 



The effect of hydrogen-ion concentration on the liquefaction of gelatin, 

 H. E. P.\TTEN and A. J. Johnson (Jour. Biol. Chem. 38 (1919), No. 1, pp. 179- 

 190, figs. 7). — Chemical and physical data, obtained at the Bureau of Chemistry, 

 U. S. Department of Agriculture, are reported which indicate that " the setting 

 of gelatin is influenced by the hydrogen-ion concentration of the medium, and 

 unless the gelatin is destroyed this effect is probably reversible. Gelatin in the 

 concentrations usetl is not without effect upon the buffer solutions, displacing 

 the pH in such a manner as one would expect from an aggregate of amino 

 acids acting amphoterically." 



Colorimetric determination of the hydrogen-ion concentration in small 

 quantities of solution, A. R. C. Haas (Jour. Biol. Chem., 38 (1919), No. 1, pp. 

 49-55). — The preparation is described of a number of indicator papers covering 

 the usual working range of pH and which can be used to determine rapidly and 



