intensities of working stresses for the wire cables were 60,000 lbs. per square inch for wire, and either one-half of the elastic limit or one-third of the

enlarge and rotate image

ultimate strength for eye-bars, the lower of the two values being adopted. The material for stiffening trusses, webs of crescent trusses, floor-systems, lateral  systems,  towers,  and anchorages was assumed to  be commercial