Source, Etc

The yellow sandal wood tree, Santalum album, Linne (N.O. Santalaceae), is a small tree distributed over India and the Malay Archipelago. It is found especially in Southern India, from Mysore to Madias, and is regularly cultivated there for the sake of its wood, which has long been used in India in religious ceremonies. It was known in Europe in the eleventh century, and has been used medicinally since the middle of the fifteenth century.

The yellow sandal wood tree is a Government monopoly in Mysore, whence nearly all the sandal wood of commerce is obtained. The tree is plentiful, but must be grown slowly in arid situations upon poor and stony soil to yield the largest proportion of oil. The tree is uprooted and roughly deprived of its bark and part of the sapwood. It is then taken to certain depots (of which there are nine in Mysore) where the trunks are sawn into lengths of about a metre and trimmed, and the roots are freed from bark. The logs are sent either direct to London or by native craft to Bombay or other ports on the west coast of India, whence they are exported to London. Periodical auctions of the wood are held in Mysore, where also a certain amount of oil is distilled.

Description

Sandal wood logs are about a metre in length and up to 15 or 20 cm. in diameter, consisting of the heartwood only of the tree. This is yellowish or pale reddish in colour, hard, heavy, and dense, but easily split. The transverse section shows alternating lighter and darker zones; the medullary rays, which are very fine and close together, are visible under a lens; the vessels are mostly solitary, being only occasionally arranged in small radial groups.

The wood has a slightly bitter taste, but strong, very fragrant odour.

In the yellow sandal wood the formation of heartwood is due to the production of a volatile oil, not, as in the case of guaiacum or red sandal wood, of a resin, or, as in the case of logwood, of a mixture of resin, tannin, and colouring matter. The volatile oil is found in all the elements of the wood; it is not secreted by or contained in any particular cells or glands.

The student should observe

(a) The pale colour,

(b) The characteristic odour and taste,

(c) The vessels usually single.

Constituents

The only important constituent of the wood is the volatile oil (sp. gr. 0.973 to 0.985; O.R- 13° to - 21°), of which it yields from 2 to 5 per cent. The chief constituent of the oil is the alcohol santalol, C15H160, (probably a mixture of a- and β-santalols), of which it contains over 90 per cent.

Uses

The wood is used as a source of the volatile oil, and technically for the manufacture of various articles. Sandal wood oil is a stimulant and disinfectant of the whole genito-urinary tract.

Varieties

West Indian Sandal wood, Amyris balsamifera, Linne (N.O. Burseraceoe); vessels in radial groups; sp. gr. of volatile oil

0.960 to 0.967; O.R. + 24° to + 29°; contains 50 per cent. of amyrol).

West Australian Sandal wood, Fusanus spicatus, Robert Brown (N.O. Santalaceae); vessels in radial groups; sp. gr. of volatile oil 0.953 to 0.965; O.R. + 5°; contains 75 per cent. of santalol.

South Australian Sandal wood, Santalum Preissianum, Miquel (=Fusanus acuminatus, Robert Brown); sp. gr. of volatile oil 1.022; rose-like odour.

Fiji Sandal wood, Santalum Freycinetianum, Gaudich (= S. Yasi, Seem.); sp. gr. of volatile oil 0.9768; O.R. - 25.5°; odour slight.

Several other fragrant woods are known, e.g. those of Osyris tenuifolia, (N.O. Santalaceoe) from East Africa; Olearia Traversii, F. Mueller (N.O. Compositae) New Zealand; Brachyleana Hutchinsii, Hutchinson (N.O. Compositoe), Nairobi.