424 ODOROGRAPHIA. i 



ester, ^vith a boiling point between 235^ and 236^. Saponification 

 of this ester resulted in the recovery of the roseol. The action of 

 dehydrating agents converted the alcohol into a hydrocarbon of 

 which the analysis responded to the formula C^q H^^, rather than 

 to that of CjoH^,;. Treated with chromic acid solution, roseol 

 oxidised into an aldehyde of a lemon or melissa-like odour. Its 

 sodium-bisulphite compound was crystalline. 



Eeformatzky and Markovnikoff believe that the stereoptene of 

 otto of rose consists of a simple hydrocarbon of the fatty series ; 

 but in this they are mistaken, for, as already proved by Messrs- 

 Schimmel, as far back as 1890,* from research into German oil 

 distilled by themselves as well as into Bulgarian otto, hydrocarbons 

 of quite different melting points ( + 22'^ and +40°) can be evolved 

 with ease from the stereoptene, if the latter be experimented upon 

 in large quantities. Hence the stereoptene cannot be a simple 

 body. 



The remaining results of Eeformatzky and Markovnikoff's 

 investigations are in contradiction with those obtained at one time 

 by Eckart. According to the latter, the alcohol which gives the 

 odour to otto of rose, answers to the formula C\(j H^^ 0, from 

 which by the separation of water, dipentene (C-^y Hj^) is formed. 

 This has recently been thoroughly confirmed by Barbier,t who 

 obtained bi-hydrochlorate of dipentene by treating rhodinol with 

 dry hydrochloric acid. From this combination he liberated the 

 dipentene, w^hich he recognised by its tetra-bromide melting at 

 124*^. Barbier also obtained the acetic ester of rhodinol. It 

 yielded back unaltered rhodinol upon saponification and possessed 

 the formula 0^0 H^. C. H3 : whereas, according to 

 Eeformatzky and Markovnikoti', its formula isC-i^H^yOCoHyO. 



German Otto of Rose. The yield of this fine product from the 

 rose plantations belonging to Messrs. Schimmel & Co. has been 

 greatly reduced (in qucintity) by the abnormal drought which 

 prevailed during the flowering season, and those parts of the land 

 which are as yet beyond the reach of artificial irrigation have 

 suffered in an exceptional degree. The October Eeport issued by 

 this firm state? that the flowers were of the choicest description, 



* Bericbt, October, 1890. 



t "Derives and constitution du rhodinol de I'essence de roses, Comptes 

 Rend us, cxvii., p. 771. 



