1911 Encyclopædia Britannica/Dammar

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DAMMAR, or Dammer (Hind, damar = resin, pitch), a resin, or rather series of resins, obtained from various coniferous trees of the genus Dammara (Agathis). East Indian dammar or cat’s eye resin is the produce of Dammara orientalis, which grows in Java, Sumatra, Borneo and other eastern islands and sometimes attains a height of 80–100 ft. It oozes in large quantities from the tree in a soft viscous state, with a highly aromatic odour, which, however, it loses as it hardens by exposure. The resin is much esteemed in oriental communities for incense-burning. Dammar is imported into England by way of Singapore; and as found in British markets it is a hard, transparent, brittle, straw-coloured resin, destitute of odour. It is readily soluble in ether, benzol and chloroform, and with oil of turpentine it forms a fine transparent varnish which dries clear, smooth and hard. The allied kauri gum, or dammar of New Zealand (Australian dammar), is produced by Dammara australis, or kauri-pine, the wood of which is used for wood paving. Much of the New Zealand resin is found fossil in circumstances analogous to the conditions under which the fossil copal of Zanzibar is obtained. Dammar is besides a generic Indian name for various other resins, which, however, are little known in western commerce. Of these the principal are black dammar (the Hindustani kala-damar), yielded by Canarium strictum, and white dammar, Indian copal, or piney varnish (sufed-damar), the produce of Vateria indica. Sal dammar (damar) is obtained from Shorea robusta; Hopea micrantha is the source of rock dammar (the Malay dammer-batu); and other species yield resins which are similarly named and differ little in physical properties.