l622 MEDICINAL PLANTS 



leaves of E. Globulus yielded i.i per cent of oil, dried leaves gave 2 per 

 cent ;in E. vininalis the figures were 0.6 per cent 1.24 per cent respectively. 

 The drjang of the leaves also resulted in smaller quantities of condensation 

 water, so that the expense of fuel for distillation was less. On the other 

 hand, dessi cation did not cause any loss of essential oil. 



From the chemical standpoint E. Globuhts, E. Maideni and E. pulveru- 

 lenta may be classed together, as they yield very similar oils, containing 

 over 40 per cent eucalj^ptol. It has been proved that these three species 

 will grow well on the coast of Balum and that the}^ can be cultivated on 

 a large scale. The total leafage of E. Maideni is heavier than that of 

 E. Globulus. This fact, together with the higher oil yield of the former 

 species, must have some effect on the return from its cultivation. It has 

 also been proved that the eucalyptus oil obtained from the Batum coast 

 is not inferior in quality to that derived from other countries ; on the 

 contrary, for E. Globulus and E. Maideni the qualitj^ is superior. 



The probable expenses and receipts of the production and commer- 

 cial extraction of essential oils may be summarised thus : capital for laying 

 out plantations £ 19 per acre ; annual expenditure about £ 8 per acre ; a 

 return of £ 19 4s to £ 22 ^s per acre may be expected, representing interest 

 at the rate of 13 to 30 per cent on a capital of £ 2600 to £ 3200, laid out 

 on 25 to 50 acres of land and on the building of the factory. 



Other interesting investigations have been made on wild mint {Mentha 

 Pulegiwn) and Castor oil. The results are quite satisfactory ; the yield 

 of essential oil from fresh mint was 0.4 per cent, and after diydng in the 

 air 1.09 per cent ; in castor oil seeds the proportion of oil reached 49.5 per cent. 



By using the fresh leaves of a tree of Cinnamomum Camphora Nees. 

 (about 20 years old), 0.9 per cent of raw camphor was obtained; 22.6 per 

 cent of the total quantity consisted of oil of camphor, the remaining 77.4 

 per cent being camphor. Experiments with large branches i ^ to 2 in- 

 ches in diameter, gave negative results; no separation of solid camphor 

 took place, but a small quantitj^ (0.09 per cent) was obtained of an oleagi- 

 nous substance with a peculiar smell which recalled that of camphor, (i), 



(i) According to Prof. Giglioli the distribution of camphor in the different parts of 

 Cinnamomum Camphora growing in Italj' is as follows : 



" It thus appears that only the foliage of the camphor tree should be used, the oldest 

 leaves being taken by preference and dried. This applies at any rate, to those trees 

 which are similar in species to those that are beconing less and less frequent in the forest 

 of Japan and Formosa,,. {.Ed.). 



