11,700. Remarks. The bitter bark contains medicinal properties valued in bronchitis and other troubles. The fruit, agreeable when ripe, is also used in medicines and cordials. [p115] [Illustration: WILD BLACK CHERRY (_Prunus serotina_).] [Illustration: PLATE 24. TEAK AND GREENHEART (_Tectona_, _Nectandra_, etc.). Greenheart (_Nectandra rodiali_). Teak (_Tectona grandis_). Teak Tree. Teakwood. Lignumvitæ Wood.] TEAK. GREENHEART. (_Tectona_.) (_Nectandra_.) There are two Teaks; the principal one (_Tectona grandis_), a native of Asia, has been called the "Oak" of the Indian forests, the other (_Oldfieldia africana_) is an African tree.[60] The Greenheart (_Nectandra rodiali_) is of the laurel family and grows in South America. The woods, although foreign, are of such nature as to have widely established reputations, and each has at some time been used in construction. Teak suggests oak, save that it is lighter and has a more uniform structure. It is very durable, and an oily secretion repels insects and preserves iron fastenings. During the supremacy of wooden vessels it was regarded as one of the best ship-building woods in existence. The grain fits it for carvings, and it is now known in North America chiefly because of this fact. Indian teak is the wood usually referred to. Greenheart was early placed among the first class of ship-building woods by Lloyd's Register, and is yet taken to Europe to some extent for dock-and ship-building and for implements, but is seldom found and but little known in the United States. It is strong, hard, durable, and extremely heavy, the latter quality being so pronounced as to limit its field of usefulness. [p116] FOOTNOTE [Footnote 60: It was long supposed that African teak was supplied by the species Swietenia senegalensis. It is now known that the source is Oldfieldia africana, of the family Euphorbiaceæ. It is not impossible that wood passing as teak may be derived from yet other species.] TEAK. _Tectona grandis._ Nomenclature. Teak. Indian Oak. Teek. Sagwan. Locality. India, Burma, Siam, Ceylon. Features of Tree. Eighty to one hundred feet in height, three to four feet in diameter, sometimes larger. Straight trunk, large drooping deciduous leaves. Color, Appearance, or Grain of Wood. Variable, brownish-yellow, straight, even-grained. Structural Qualities of Wood. Moderately hard, strong, easily worked, stands well, oily, fragrant, resists termites, preserves iron. Representative Uses of Wood. Furniture, ship-building, timbers, backing for armor-plates. Weight of Seasoned Wood in Pounds per Cubic Foot. 50 (Laslett). Modulus of Elasticity. 1,338,000 (Lazlett). 2,100,000 (Thurston). Modulus of Rupture. 15,000 (Thurston). Remarks.