USES OF EUCALYPTS. 39 



of Melbourne. Bai'on von Mueller states in the Eucalyptographia 

 that in 1880 Bosisto was producing 6 tons of oil per year. Since then 

 the demand for the oil has increased very much, and a nuich larger 

 quantity is produced in Australia annually. During the past ten 

 years considerable eucalyptus oil has been produced from the Blue 

 Gum plantations in Algeria, it having been found advantageous to 

 obtain the oil from solid plantations of one species rather than from 

 native forests where the species grow mixed. In California consider- 

 able oil has been extracted from the Blue Gum during the past five 

 years. The principal producer is a physician in Los Angeles, who is 

 attempting to establish a reputation for putting up a pure high-grade 

 product. During the winter of 1900-1901 he extracted 9 tons of oil. 

 He does not distill out any eucalyptol, as he considers the oil in the 

 form he puts it out superior for most purposes. The residue from 

 the distillation of the refined oil from the crude product is put up for 

 a salve. From the oil he manufactures a soap and cough drops. 

 Hon. Ellwood Cooper has a young Blue Gum plantation on his ranch 

 near Santa Barbara, from which he intends to manufacture both euca- 

 lyptus oil and eucalyptol. He will cut the trunk and limbs into fuel, 

 extract oil from the twigs and leaves, and thus utilize the entire tree. 



The different species vary greatly as to the amount of oil the}" will 

 yield, the range being from none to 500 ounces from 1,000 pounds of 

 fresh lea^•es and twigs. According to J. Bosisto and other Australian 

 authorities and S. M. Woodbridge, of Los Angeles, the Peppermint 

 Tree {Eucalyptus amygdalina) yields the largest amount. But in 

 America this tree is not grown extensive^ enough for it to be a source 

 of much oil. For some years yet, and perhaps always, the chief 

 source of eucalyptus oil here will be the Blue Gum. The yield of 

 crude oil from the leaves and twigs of this species ranges from 1 to 

 l.() per cent. Dr. Herron extracted, during the past season, 9 tons of 

 oil from TOO tons of leaves and twigs from this species — a yield of 

 1.28 per cent. H. B. Silkwood, proprietor of the California Eucah'p- 

 tus Works, Garden Grove, Cal., reports that he produced 1 ton of oil 

 from 100 tons of material during the past 3'^ear, the output being 

 limited by the available supply of Blue Gum leaves. The Red Gum 

 yields much less oil than the Blue Gum — only 10 to 30 per cent as much. 



The oils from the different species of Eucalypts differ greatly. As 

 extracted they are all compounds or mixtures. The chief ingredient 

 of the oil from the Blue (jum is a colorless, transparent, camphora- 

 ceous liipiid called eucalyptol "or cineol; of the Peppermint Tree 

 {Eucaly2)tu.'< ainygddliria), a less known liquid called phellandrene; of 

 the Lemon-scented Eucalypt {E. cltriodora)^ a fragrant, highly vola- 

 tile liquid called citronellon, mixed with another fragrant licpiid called 

 geraniol. Several other ingredients enter into the composition of 

 the oils from the various species. The best known of all the ingre- 



