— 68 — 



Oil of European Pennyroyal. The scarcity of oil of European 

 Pennyroyal, which had existed since last year, has become somewhat 

 less pronounced by the arrival of the new Spanish distillate, but the 

 supply does not yet seem to equal the demand, and the prices show 

 as yet little inclination to return to their previous level. A few large 

 parcels which were recently sold had to be rejected on account of 

 defective quality. Of Algerian oil, very little comes on offer. 



The prices of American pennyroyal oil (being consumed 

 chiefly in the United States) reached the respectable height of 

 3.25 dollars per lb., which must be paid whether the purchaser likes 

 it or not. Owing to the brisk demand, with very limited stocks, the 

 distillation was commenced very early this year, and the bulk of the 

 material was w r orked up in the undeveloped state. Whilst formerly 

 North Carolina supplied most of the pennyroyal oil, the industry now 

 also receives great attention in the State of Tennessee. 



The constituents of the oil of American pennyroyal (Hedeoma 

 pulegioides L.) have been examined more in detail by Marmaduke 

 Barrowcliff 1 ). The oil, supplied by Fritzsche Brothers, of New 

 York, had the following constants; diso 0,9297; «d-J-2 5°44'; soluble 

 in 2 vol. 70 per cent, alcohol. Of free acids there were detected 

 in the oil, formic, butyric, octylic, and decylic acids. By extraction 

 with 5 per cent, caustic potash liquor, Barrowcliff obtained 

 small quantities of a not further examined phenol, and also traces 

 of salicylic acid, which was probably present in the oil in the form 

 of the methyl ester. From the portions of the oil boiling above 120 

 (60 mm.), pulegone (24,1 °/ of the oil) was isolated by bisulphite 

 solution, and identified by the melting point of the semicarbazone (171 ). 

 The portion treated with bisulphite was saponified, the oil obtained 

 was distilled at 60 mm., and then distilled at ordinary pressure jointly 

 with the portions boiling below 120 (60 mm.) of the oil extracted with 

 soda solution and caustic potash liquor. In the fraction of 155 to 165 

 thus obtained were detected small quantities of 1-pinene, in the fraction 

 passing over at 165 to 170 i-methyl-3-cyclohexanone (8°/ ) which 

 after regeneration from the semicarbazone (m. p. 182 to 183 ) distilled 

 at 167 to 1 68°; this appears to be the first time that the presence 

 of this ketone has been observed in nature. The same fraction and 

 also the next fraction of 170 to 180 , contained small quantities of 

 1-limonene and dipentene. 



After small quantities of pulegone had still been worked out from 

 the fraction passing over at 212 to 217 , the purified fraction was 

 employed for producing semicarbazones , when it was found possible 



*) Journ. chem. Soc. 91 (1907), 875. 



