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Cole, Timothy

(Encyclopedia)Cole, Timothy, 1852–1931, American wood engraver, b. London. He came to the United States as a child. Cole learned his trade in Chicago and later moved to New York, where in 1873 he began his 40-yea...

tugboat

(Encyclopedia)tugboat, small, strongly built vessel, used to guide large oceangoing ships into and out of port and to tow barges, dredging and salvage equipment, and disabled vessels. Tugboats range in overall leng...

pyroligneous acid

(Encyclopedia)pyroligneous acid pīˌrəlĭgˈnēəs [key], a dark liquid that is essentially a mixture of acetic acid and methanol (wood alcohol) and is obtained in the destructive distillation of wood. It once se...

tar and pitch

(Encyclopedia)tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of w...

vascular bundle

(Encyclopedia)vascular bundle, in botany, a strand of conducting tissue extending lengthwise through the stems and roots of higher plants, including the ferns, fern allies, gymnosperms, and angiosperms. The vascula...

herbaceous plant

(Encyclopedia)herbaceous plant hûrbāˈshəs [key], plant whose stem is soft and green and shows little growth of wood. The term is used to distinguish such plants from woody plants. Herbaceous plants, or herbs, a...

ash, in chemistry

(Encyclopedia)ash, in chemistry, solid residue of combustion. The chemical composition of an ash depends on that of the substance burned. Wood ash contains metal carbonates (e.g., potassium carbonate) and oxides fo...

sapwood

(Encyclopedia)sapwood, relatively thin, youngest, outer part of the woody stem of a tree, the part that conducts water and dissolved materials. In the cross section of a tree, the sapwood is recognizable by its tex...

centering

(Encyclopedia)centering, the framework of wood or of wood and steel built to support a masonry arch or vault during its construction. The centering itself must be rigidly supported, either by posts from the ground ...

heartwood

(Encyclopedia)heartwood, the central, woody core of a tree, no longer serving for the conduction of water and dissolved minerals; heartwood is usually denser and darker in color than the outer sapwood. Before the s...