BENZOIN  , or

Gum BENJAMIN (supposed to be from Arab. luban, frankincense, the first syllable being dropped in Romanic as if it were the article), a balsamic resin obtained from Styrax benzoin, a tree of considerable size, native to Sumatra and Java, and from other species of Styrax . It is obtained by making incisions in the bark of the trees, and appears to be formed as the result of the wound, not to be secreted normally . There are several varieties of benzoin in commerce: (1) Siam benzoin, which apparently does not come from Styrax benzoin, is the finest and most aromatic, and occurs in the form of small " tears, " rarely exceeding 2 in. in length by 1 in. in thickness, and of " blocks " made up of these tears agglomerated by a clear reddish-brown resin . The odour of Siam benzoin is partly due to the presence of vanillin, and the substance contains as much as 38 % of benzoic acid but no cinnamic acid . (2) Sumatra benzoin occurs only in masses formed of dull red resin enclosing white tears . It contains about 20 % of cinnamic acid in addition to 18 or even more of benzoic . (3) Palembang benzoin, an inferior variety, said to be obtained from Styrax benzoin in Sumatra, consists of greyish translucent resinous masses, containing small white opaque tears . It does not appear to contain cinnamic acid . Large quantities of benzoin are used as incense . Its medicinal uses depend on the contained benzoic acid (q.v.) .