Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

534 MOLESWORTH’S POCKET-BOOK Breast and Overshot Wheels—continued. Forms of Buckets (Cubved). D = Depth of shrouding. d = Distance of buckets apart at periphery. S = Length of start (radial). X = Angle of radius of bucket curve, with radial line of wheel at. points of bucket. = Length of bucket curve, measured on periphery of wheel. 1' = d. S = J D. Z = i| D in large wheels. I — D in wheels under 25 feet diameter. . X = 15° in overshot or high-breast wheels. X = 25° in low-breast wheels. The radius of the bucket curves may b determined thus From the point Of the bucket A set off the line E A at the angle X, with the radius of the wheel. Draw the start C B = | E depth of shrouding. Join A. B and bisect the line ? AB at D, and raise the / perpendicular DE. The u—•——5 points of intersection of D E with A E will be the centre from which the bucket curve will be struck with the radius AE. In prac- tice the start is rounded, as shown by the dotted line between B C.