The approximate London market value of guaiacum is 9d.-3s. 6d. a lb.
A so-called " guaiacum" from Peru, recently imported for perfumery purposes, would seem to be a distinct product.
Gurjun-balsam or Wood-oil.—This oleo-resin, whose second name must not be confounded with the fatty oil bearing tho same appellation, described on pp. 1411-2, is obtained from eeveral speckle of Dipterocarpus. The most important are D. turbinatus [items, indicus] of E. Bengal, Chittagong, Pegu, Singapore, and Frenoh Cochin China, and D. trinervis of Java and the Philip pines. Other speciee of minor significance are :—D. incanus of Chittagong and Pegu ; D. abitus of Chittagong, Burma, Tenasserim, the Andamans, Siam, and Cochin Chiva ; D. erispa/atus of French Cochin China; D. zeylanicus and D. hispidus of Ceylon ; aud D. gractits, D. littoralis, and D. retusus [Spanoghei] of Java.
The extraction of the oleo-resin seems to be everywhere performed in the same manner. The operation mainly consists in scooping a basin-like hole out of tbe trunk of the tree at a convenient height above the ground, and periodically igniting a fire within the cavity. The heat causes the balsam to flow from the ducts containing it aud to collect in the basin, whence it may be dipped or siphoned into receptacles. The tapping is effected at about the end of the dry season, or during November-Fehruary. Every 3-4 weeks, the charred surface of the cavity is chipped away, and a fresh flre is made. In large healthy trees, eometimee a eecond cavity is cut. Trees which appear sickly in the following season are allowed a year or two'e rest. Good trees give an average yield of 30-40 gal. during the season. The oleo-resin as extracted is allowed to settle, in order that the clear liquid portion may free itself from the thick sedimeut or guad.
Thu balsam, being derived from several different trees and various countries, does not exhibit a constancy of character, It may be generally described as a viscid fluid consisting of about 31 per cent. of resin, and 65 of essential oil, highly fluorescent, transparent, and dark .reddieh-brown against the light, resembling copaiba in odour, flavour, and medicinal properties, but' giving 'no unpleasant smell to the breath. Its sp. gr. is 0.964 at 17° (621° F.) It is quite soluble in pure
benzol, curnol, chloroform, carbon bisulphide,,and essential oils ; partially in methylic, ethylic, and amylic alcohols, ether, acetic ether, glacial acetic acid, acetone, carbolic acid, absolute alcohol, solution of caustic potasb, many samples of commercial benzine, and petroleum-ether. Tests which distinguish it from copaiba have been given on p. 1640.
Gurjun is produced in Cannra (S. India) in small quantity. It is exported from Singapore, Moulmein, Akyab, and the Malay Peninsula, and is a common article of commerce in Siam. It occurs abundantly in Samar and Albay, and probably other provinces of the Philippines, where it is known as balao or malapajo; it is sold in Albay at the rate of 4 reals per tinaja of 10 gantas (say 4/d. a pint). It is now regularly to be met with at the London drug sales. Medicinally, it is employed in skin-diseases in England, and as a, substitute for copaiba in India. In the Philip pines, and other localities of production, it has more importance as a varnish (best after boiling to remove the essential oil), an ingredient of lithographic inks, a preservative for iron (against rust) and for timber (against termites and other insects), and generally for application to the seams and bottoms of boats and ships. As a varnish, it is reported to dry slowly and possess little body, but the case might be different if the essential oil were boiled off.
See also Copaiba, p. 1639; Hardwickia, p. 1654.
auttapercha.—This name, as naturalized in European commerce, embraces the inspissated juices of several species of sapotaceous trees growing wild in peninsular and insular Malaysia. Their range has been defined as lying between 6° N. and S. of the equator, and between woo and 120° E. long.; this has been more recently curtailed to 4° N. and 3° S. lat., the finer varieties being confined between 3° 50' N. and 1° S. lat., where the air is very humid, and the temperature ranges about 19°-32° (66°-90° F.).