SCIENTIFIC AND omer NOTES ON ESSENTIAL OILS. — | 37 
_ Palmarosa Oil. We escent at the time an article by R. S. Pearson’) on the 
Rosha oil industry in British India, mentioning that the author thought it possible to raise 
the annual production from about .150000 to 225000 Ibs. by introducing the steam 
di stillation, but that it was doubtful, whether the market could take up such a quantity 
vithout there being a considerable fall in price. 
_ Trials have now been made on a small scale, in the. Melghat Division, in order to 
ob = palmarosa or gingergrass oil by steam distillation. So far, nothing is known 
about the results*). : . 
_ Patchouly Oil. Gok. Logan*) has published a short notice on the production of 
p Bictioaly oil in the Straits Settlements, from which we copy the following particulars: — 
The patchouly plant (Pogostemon Patchouli, Pell.; Labiat) is often planted by the Chinese 
‘ir places where the forest has been recently cleared. A little shaded, it grows there 
fairly quickly and luxuriantly between the trunks of the felled trees. Where it is really cul- 
tivated; it is planted on properly prepared beds. It is best propagated by slips from young 
; hoots. They must be about 7.5 cm. long and cut just underneath a knot. They are 
put in frames, well watered and shaded. After 3 or 4 weeks, they have formed roots, 
so that they can be transplanted to the proper beds, where they must be shaded till 
they have rooted. It is true, the plant can be cultivated too in the sun, but a little 
‘shadow is advantageous. The distance between the slips is about 2 feet. 
a The first crop takes place six months after planting and is then repeated twice 
P early. In Perah, the plantations are renewed after three crops. é 
Spread out in the shadow, the leaves get dry in about a week’s time. A picul 
(1334/3 Ibs.) of leaves dried immediately after having been gathered, yielded from 24 to 
39 ozs. of essential oil; a sample without stalks, about double the quantity. From 
3/20 acre, 449 lbs. of green herb were gathered, corresponding to 106 lbs. of dry material, 
ev which yielded 69 lbs. of good leaves and 37 Ibs. of refuse. 
The dry patchouly leaves are exported principally to Marseilles tad New York. In 
1916, nearly all the exports of Penang went to New York, the quantity being 65 tons. 
In 1917, the total exports of patchouly leaves from Penang to the United States 
amounted to 79979 Ibs. to the value of §' 12252 gold. 
As to patchouly- growing in the Dutch East Indies, see p. 82 of this Report. 
Pemayreyal Oil. Oil of F ncrmigroval (irom Hedeoma pulegioides [L.], ee Labiat®) is 
or ie of the few oils containing pulegone. According to Barrowcliff’s latest investigation‘), 
the oil contains, in addition to pulegone, /- Hite 3-cyclohexanone, i-menthone and 
¢ i-isomenthone. If therefore 80 to 90 per cent. of “pulegone” are found by the sulphite 
me thod, this figure refers to the mixture of ketones mentioned, as C. T. Bennett°) 
points out, 
The pennyroyal ketones are absorbed far more slowly by the sulphite than those 
of other essential oils, such as caraway and dill oils, and shaking must be continued 
about three hours, as otherwise the figures arrived at would be too low. In one 
instance, the ketone content found was 44 per cent. after one hour’s shaking with the 
sulphite solution, 58 per cent. ah the second hour and 88 per cent. after three hours. 
yy The Indian Trade E oiinighe Indische Mercuur 89 (1918), 787; Report October 1917,-31. — 2) Perfium. 
+ cord 9 (1918), 208. — *) Commerce Reports of September 1918, Americ. Journ. Pharm. 90 (1918), 733. — 
) Comp. Gildemeister and Hoffmann, The Volatile Oils, 2°4 ed., vol. HI, p. 467. — 5) Perfum. Record 9 
(1918), 208. ! , 
