Rankine, William John Macquorn, 1820-1872, Millar, William J, Tait, Peter Guthrie, 1831-1901 · London, C. Griffin and company · leaf 553
pectto x, already referred to, is performed as follows:—The co-ordinates of aparticle of water being x and y, let x denote the position of a movablepoint in the axis of a: then the function to be integrated is (X - */)« + f for all values of x between two arbitrary limits. Let 2a denote thedistance… … ON PLANE WATER-LINES. 501 x = + a , . ^-—5 » = tan 1 \- tan x . (18.) (x-x)2 + y2 y y a / a This quantity evidently denotes the angle contained between two linesdrawn from the point (x, y) to the points (+a, 0) and (—a, 0). Forbrevitys sake, in the sequel that angle will be occasionally denoted by…
