— 2 4 — 



does not supply camphor seed to any private people, who are able to 

 obtain their requirements of such seed from the trees which had already 

 previously been planted in Florida and California. In most of the plant* 

 ations the trees are regarded only as ornamental, and are treated as 

 such, but in some of them experiments have been made to obtain camphor 

 by distilling the leaves, either with or without stalks. The results of these 

 experiments are not reported by the author, who only deals with his 

 own experiments in making industrial use of the Californian camphor 

 tree. According to these experiments, mature green leaves yield about 

 i per cent, by weight of camphor, and it is to be noted that leaves 

 and green twigs contain more liquid oil and less solid camphor. Up 

 to the present no higher yields of camphor have been obtained. 

 Hilgard observes that he has experimented only with trees growing 

 in the misty, cool climate of the coast, and not with trees from the 

 warmer and higher altitudes, for instance those from the interior of 

 California. Although the latter trees no doubt might promise a higher 

 output, seeing that odoriferous plants such as jasmine, mignonette, 

 and heliotrope also flourish in the interior of California, Hilgard 

 refrained from making any far-going experiments, because of the ex- 

 cessively high wages (for the harvesting of the leaves), which in those 

 districts are an obstacle in the way of the development of the camphor 

 industry as well as of other industries. The author therefore agrees with 

 Riviere that there is no question of any American industrial com- 

 petition with the natural riches and low wages of the island of 

 Formosa, particularly as just at the present time the prices for crude 

 camphor are low and are likely to remain so. 



With regard to the prospects of synthetic camphor, Hilgard is 

 of opinion that any serious competition with the natural product is 

 out of the question until there has been a considerable increase in 

 the present moderate yield, which equals only 2 5°/ of the turpen- 

 tine oil used. Moreover, account has to be taken of the quickly 

 progressing exhaustion of the American turpentine forests. Hilgard 

 conjures up a future vision of the preparation of camphor from petroleum, 

 which is certainly a distant prospect and not a very credible one at 

 the present time. At any rate, the experiments which have for their 

 object the replacement of camphor by similar materials have much 

 more chance of being realised. 



In an appendix to the paper, Cay la lays stress upon the complete 

 agreement of Hilgard with the views frequently expressed by him 

 (Cay la), to which we have referred in previous Reports. Cay la regards 

 Hilgard's statements as an indirect confirmation of the conclusions 

 arrived at by Giglioli 1 ), insofar as the latter particularly referred to the 



*) Report November 1908, 36. 



