ECONOMIC BOTANY. 129 



preparations of the bark and alkaloids are made, and used 

 medicinally as tonics and febrifuges. 



18. Wood, the lignified stems, trunks, and branches of 

 Gymnosperms (as Pines, etc.) and of Dicotyls, is used in 

 architecture, ship-building, manufacture of vehicles, machines, 

 implements, tools, furniture, ornaments, in the construction of 

 bridges, fences, for fuel, etc. A great variety as regards color, 

 strength, hardness, weight, porosity, durability, flexibility, are 

 offered by the numerous species of woody plants. Some of 

 our most important kinds of wood or indigenous timber trees 

 are the Pines, Cedars, Redwood, Larch, Cypress, the Maples, 

 Yellow Poplar, Honey Locust, Ash, Elm, Walnut, Chestnut, 

 Hickories, Oaks, etc. Of foreign woods very important kinds 

 found in commerce are Mahogany, Teak, Logwood, Brazil- 

 wood, Red Sandal-wood, Boxwood, Ebony, etc. 



19. Curcuma longa, a member of the Ginger family (Zingi- 

 beracex), is a native of Southern Asia, and is cultivated in 

 India, Ceylon, Java, the West Indies, etc. Many different va- 

 rieties have arisen under cultivation. They furnish the dye 

 Turmeric in varying qualities. Turmeric (the yellow rhi- 

 zome) is used in dyeing paper, wood and leather, and in color- 

 ing varnishes. It is mucli used in cookery, also in medicine. 

 Turmeric paper, or unsized paper colored with a decoction of 

 turmeric, is used in the chemical laboratory as a test for free 

 alkali and acid. The Ginger plant. Zingiber officinale (family 

 Zingiberacex), has been cultivated from time immemorial in 

 India, in which country it is probably indigenous. It has re- 

 cently come into cultivation in the West Indies and other 

 tropical lands. It is an annual plant, with stems two or three 

 feet high and leaves two or three inches long. The flowers 

 are yellowish, and have an aromatic odor. The rhizome, pow- 

 dered or otherwise, constitutes the Ginger of commerce. It 

 contains volatile oil, starch, resin, etc. The sweet flag (^Acorus 

 calamus) has a fleshy aromatic rhizome called Calamus, well 

 known and extensively used in Europe, Asia and North Amer- 

 ica. It grows in marshy or wet places. 



20. The Tea plant. Camellia chinensis (family Turnstroemi- 



