The American house carpenter. A treatise on the art of building. Comprising styles of architecture, strength of materials, and the theory and practice of the construction of floors, framed girders, roof trusses, rolled-iron beams, tubular-iron girders, cast-iron girders, stairs, doors, windows, mouldings, and cornices; together with a compend of mathematics. A manual for the practical use of architects, carpenters, stair-builders, and others (1880)
Hatfield, R. G. (Robert Griffith), 1815-1879, Hatfield, O. P., ed · New York, J. Wiley & sons · leaf 519
r of the polygon. Now, if for the perimeter of the polygon there be sub- 476 THE CIRCLE. stitiited the circumference of the circle, we shall have, put-ting for the circumference 3-1416 d, or, n d {Art. 446)— A =^7tdr, in which r is the radius. Since 2 r — d, the diameter, and r = -, we have- 2 And… … D Fig. 297. As an example, the area of a circle 10 feet in diameter isfound thus— 10 X 10 = 100. 100 X 0-7854 = 78-54 feet. 449.—Circle: Area of a Sector.—The area oi A B CD{Fig. 297), a sector of a circle, is proportionate to that of thewhole circle. For, as the circumference of the whole circleis…
Carpentry · Architecture · Building
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
