Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

287 Molesworth’s pocket-book. High Dams in Masonry for Reservoirs. H = Height of dam In feet. x = Any depth below the surface of water in feet. y = Offset from vertical line to outer face of dam at any depth, x in feet. z = Ditto, ditto to inner face in feet. b = Width of dam at top in feet. c = Width of dam at from top in feet. — 1 • 1 y when x = | H. P = Limit of pressure allowed on the masonry in lbs. per square foot = 12,300 lbs. in the Furens Dam: = 16,400 lbs. per square foot in the Dam de Ban. If y as given by the formula is less than 0 • 6 x, it must be increased to 0'6 x. In very high dams P should be gradually dinri* nisi æd as the depth increases by substituting p for P, p being = P — (• 0013 P x~). The formula above given can only be considered approximate.