AGRICULTURAL CHEMISTRY AGROTECIINY. 309 



The experiments were conducted with niontanin, which is an aqueous solution, 

 strongly acid, and almost odorless, bavins ;i specific gravity of 1.3502 (38.1° 

 Baume at 15° C). It consi.sts essentially of a solution of free silicofluoric acid 

 (about 23 per cent) and zinc aluniiuum silicofluorid (20 to 30 per cent). 

 Hydrofluoric acid and hydrofluosilicic acid are considered good preservatives, 

 especially for wood. 



The coloring matters of blossoms and fruits, R. Willstatteb (Sitzber. E. 

 Prenss. Aknd. Wiss., 1914, A7/, pp. 402-411; abs. in Chem. Ztg., 38 {1914), 

 Ko. 48, p. 516). — A number of anthocyanins of blossoms and fruits were isolated 

 in a crystalline condition. They are considered sugar combinations of coloring 

 matters and are recognized as hydroxy} combinations of a phenylbeuzopyrylium. 

 The anthocyanins are chinoids of oxouium salts. They form a new class of 

 plant bases whoso basic nature is due to tetravalent oxygen. 



The constituents of Solanum angustifolium: Isolation of a new gluco- 

 alkaloid, solaugustin, F. Tutin and H. W. B. Cleweb (Jour. Chem. Soc. 

 [London], 105 (.1914), No. 617, pp. 559-576).— In Peru. Bolivia, Paraguay, and 

 the southern portion of the Province of Buenos Aires, Argentina, a solanaceous 

 plant occurs which is known as " Duraznillo Blanco," and identified as 8. angiis- 

 tifoUum. It is employed in South America as a febrifuge, chiefly in the treat- 

 ment of enteric fever. In Peru it is also used in cases of malaria, but with 

 caution, on account of its reputed poisonous properties. 



In the work reported, " from the portion of the extract which was soluble in 

 water there were isolated the following substances: (1) Quercetin; (2) rutin, 

 CaTHsoOio.SUsO ; (3) 1-asparagiu ; (4) a new gluco-alkaloid, solangustin, 

 C33H5307X,H:;0. On hydrolysis, solangustin yields solaugustidin, C27H4302N, to- 

 gether with one molecule of dextrose. The aqueous liquid also contained small 

 amounts of amorphous, alkaloidal material, and a considerable quantity of a 

 sugar, which apparently was levulose. together with viscid, amorphous products. 

 Some of the latter yielded quercetin and 3: 4 dihydroxycinnaniic acid on treat- 

 ment with alkalLs. 



" The portion of the original extract which was insoluble in water yielded, in 

 addition to much chlorophyll and resinous material, the following compounds : 

 (1) Triacontane, C30H62; (2) a phytosterol, C27H4eO ; (3) a phytosterolin (phy- 

 tosterol glucosid), CssHsoOe; (4) palmitic, stearic, chiytinic, and cerotic acids, 

 together with a mixture of linoleic and linolenic acids. It furthermore gave a 

 small amount of the above-mentioned new gluco-alkaloid, solangustin, and a 

 higher fatty acid, which was either melissic acid, C3oH(io02, or a lower homologue, 

 asHooO.. 



"An amount of the total alcoholic extract, equivalent to 3.5 gm. of the drug, 

 and 0.48 gm. of solangustin were separately administered to a dog, but no 

 perceptible effect of any kind resulted. The amorphous alkaloidal material, 

 which occurred to a small extent in the plant, yielded a similarly negative 

 result." 



Befractometry, I and II, G. A. Shook (MetaUnrg. and Chem. Engin., 12 

 {1914), Ao,s'. 9. pp. 572-576, figs. 3; 10, pp. 630-6.35, figs. iO).— Part 1 of this 

 article deals with the fundamental principles of refractometry. Part 2 con- 

 •siders in detail the various instruments used in refractometry (butyro. Abbe, 

 Zeiss immersion, Pulfrich, and Fery refractometers) and the principles under- 

 lying their use. 



Determination of nitrogen by the Kjeldahl method with the aid of 

 vanadium pentoxid, Oefele {Pharm. Zenfralhalle, 52 {1911), Ao. 42, PP- 1121, 

 1122). — For each digestion 0.1 gm. of vanadium pentoxid is emi>loyed instead of 

 other oxygen transmitters. Care must be exercised at the outset in heating 

 in order to prevent overfoaming. 



