SECTION XX 



CAMPHOR 



Source, &c. Camphor is a crystalline substance contained in the 

 volatile oil of the camphor tree, Cinnamomum C amphora, Linne 

 (N.O. Laurinece), a large tree indigenous to the island of Formosa, 

 and to Japan and China. It is cultivated also in Ceylon, the Federated 

 Malay States, India, Burma, Java, East and West Africa, California, 

 &c. The leaf, petiole, bark, wood, and pith of the tree contain 

 numerous oil cells. In these a volatile oil is secreted which, by oxida- 

 tion, yields camphor. It is also found in the solid state in cavities 

 in the trunk, probably as the result of slow volatilisation and oxidation 

 of the oil. The yield of oil varies from 2 to 6 per cent, and that of 

 the camphor from 0*2 to 3 per cent., old trunks containing the most. 



Production. Camphor is usually obtained by passing a current 

 of steam through the chipped wood of the trunk and root, a primitive 

 form of still being used for the purpose. From the pasty mixture 

 of solid camphor and liquid volatile oil obtained the camphor is 

 separated by pressing. The oil is exported under the name of camphor 

 oil ; by fractional distillation is yields light camphor oil (boiling- 

 point, 175 to 200) consisting of pinene, phellandrene, cineol and 

 dipentene, and heavy camphor oil (boiling-point 200 to 275) con- 

 taining safrol and eugenol, and utilised for the production of the former 

 on the large scale. The crude camphor is purified by mixing it with 

 lime, charcoal, &c., and subliming it in large glass flasks (bomboloes) ; 

 the camphor sublimes in the upper part of the flask and is obtained 

 in the form of a thick ring by cracking the flask. It may also be 

 sublimed into flat cakes or, by passing the vapour into large cooled 

 chambers, into small crystals (flowers of camphor) which may be 

 pressed into rectangular cakes by hydraulic pressure. 



Description. Camphor occurs in small, colourless crystals or in 

 translucent, fibrous or crystalline masses with a characteristic pene- 

 trating and pungent, bitterish taste, followed by a sensation of cold. 

 It burns readily with a bright, smoky flame, and is volatile at ordinary 

 temperatures. It is a ketone, yielding isoborneol by reduction and 



