I — 133 — 



E. Deussen l ) has worked out a method which — as he says himself — 

 is based on limited experimental material only and which makes it possible 

 in several, if not in many, cases to test the purity of optically active 

 substances. He examined /^-caryophyllene nitrosite, caryophyllene glycol, 

 caryophyllene nitrolanilide, and cadinene hydrochloride, taking two pre- 

 parations of different m. p. of each compound. As sources of illumination 

 he employed sodium-light of 589 ^ and mercury-light of 491 ^. He tested 

 /^-caryophyllene nitrosite, m. p. 115 and 113,5° (the second sample being 

 therefore impure) and determined the specific rotation of different con- 

 centrations of each of these two samples, doing the same with the other 

 compounds. These investigations showed that the impurities or admixtures 

 contained in the nitrosite and glycol are optically active, whereas those 

 contained in the nitrolanilide are in all probability inactive. 



It would lead us too far here to discuss also the other peculiarities 

 mentioned by the author in the course of his comments on his tables, in 

 particular because it is extremely difficult properly to judge the values 

 given. This is perhaps due in part to the fact that the various compounds 

 have been taken in very different concentrations. 



In conclusion the author observes that his method is also serviceable 

 in the testing of terpene derivatives, alkaloids, albuminous substances, and 

 similar bodies. 



Deussen has brought together the result of his observations in the 

 form of 4 tables. In perusing these tables he has arrived at the con- 

 clusion "that the result not only claims to be of special, but also probably 

 of general, interest". 



On the action of light upon isoeugenol and upon vanillin see pp.162 

 and 127. 



Pharmaco'physiological Notes. 



Several investigators have recently been engaged in exploring the 

 disinfecting and narcotic action of the essential oils and their constituents. 

 In our Report of April 1911, p. 157, for example, we discussed a paper 

 by W. H. Martindale on the antiseptic action of essential oils, and in our 

 Report of October 1911, p. 123, we referred to a publication by Coupin on 

 ( the influence of certain volatile bodies on the development of germinating 

 grains of cereals. In our Bericht April 1911 we published, as a supple- 

 ment, an article by R. Geinitz on the action of z^-p-menthenone-S, a body 

 the presence of which in Japanese peppermint oil had been detected by 

 us. The last-named author has since published a paper under the title 

 "Vergleichende Versuche tiber die narkotischen und desinfizierenden Wir- 

 kungen der gangbarsten atherischen die und deren wirksamen Bestandteile" 



!) Journ. f. prakt. Chem. II. 85 (1912), 484. 



