218 



THE ALUMNI JOURNAL. 



ing constitutent (or its lead salt) is prin- 

 cipally contained in the last fractions, 

 and represents but a small proportion of 

 the original material. It was observed 

 that the conversion of the crotonoleic 

 acid into a lead salt did appreciably affect 

 its vesicating power. 



The supposed active constituent of 

 croton oil, crotonoleic acid, having thus 

 been shown to be a mixture, the authors 

 proceeded to attempt to isolate the vesi- 

 cating constituent from croton oil direct. 



By saponifying that part of the croton 

 oil which is soluble in strong alcohol 

 with a mixture of lead ox'de and water, 

 and repeatedly fractionating an alcoholic 

 solution of the lead salts with water, the 

 later fractions, which possessed the great- 

 est vesicating power, ultimately furnished 

 when submitted to a series of fractiona- 

 tions, a resinous substance having extra- 

 ordinary power as a vesicant. This sub- 

 stance could not be farther resolved by 

 repeating the process of fractional precip- 

 itation of the alcoholic solution with 

 water. The same substance was isolated 

 from the so-called "crotonoleic acid," 

 and the authors propose to name it " cro- 

 ton-resin." To its presence the vesicat- 

 ing property of croton oil is due. The 

 composition of croton-resin is expressed 

 by the empirical formula C, 3 H 18 0>. So 

 far all attempts to crystallize it, or to ob- 

 tain crystalline derivatives from it, have 

 been unsuccessful. It is a hard, pale 

 yellow, brittle resin, nearly insoluble in 

 water, light petroleum, and benzine, but 

 readily dissolved by alcohol, ether and 

 chloroform. When heated it gradually 

 softens, and is quite fluid at 90 C. Cro- 

 ton-resin has neither basic nor acidic pro- 

 perties ; it may be boiled with a mixture 

 of lead oxide and water without being 

 appreciably affected. Ebullition with 



* Abstract ot a communication to the Roval Society. 

 By Wyndham R. Dunstau, M. A., F. R. S.I Sec. C S., 

 and Miss h. E. Boole, F. I. C, Lecturer on Chemistry in 

 the London School of Medicine for Women. Reprinted 

 from Chem. and Drug. — Pharm. Era. 



aqueous potash or soda gradually decom- 

 poses it, destroying its vesicating power. 

 The products of this action are several 

 acids, some of which are members of the 

 acetic series. By oxidation of the resin 

 with nitric acid a mixture of acids is ob- 

 tained. The constitution of croton-resin 

 is, therefore, complicated, and its mole- 

 cular formula would appear to be at least 

 (C 13 H 1? 4 ) 2 or C 26 H 36 CV Since it is not 

 saponified by a mixture of lead oxide and 

 water, and as no glycerol could be de- 

 tected among the products of its decom- 

 position by alkalies, it is not a glyceride, 

 and as it does react with hydroxylamine 

 or phenylhydrazine, or sodium bisulphate 

 it is probably neither a ketone nor an 

 aldehyde. The evidence so far obtained • 

 points to the conclusion that the consti- 

 tution of the vesicating constituent of 

 croton oil mav be that of a lactone or 

 anhydride of complicated structure. 



CLEVE1TE AND HELIUM. 



Resting peacefully on the broad bosom 

 of the Norwegian hills there lies the 

 mineral cleveite. It looks so uninterest- 

 ing, so utterly ordinary, that the Paleo- 

 lithic Norwegian would probably have 

 considered it too unspeakably common 

 to use for cracking open either his oj s- 

 ters or the skull of his enemy, while the 

 fighting Viking would very properly 

 have hesitated to accept it as ballast fur 

 his war ship. 



Well, the Paleolithic gentlemen and 

 the Vikings have been gathered in with 

 others of the "real old school." Peace 

 be to them ; they were men ! But we, 

 who now walk about the earth, ha\e 

 adopted a different standard of interest ; 

 and cleveite, common-looking stone as it 

 is, has carried down to us, through the 

 years, not only the " thoughts that do 

 lie too deep for tears," of Wordsworth's 

 flower, but the radiant [hope of a widen- 

 ing knowledge which will not only in- 



