William A. Radford · Radford Architectural Company · leaf 9
are made by cutting theround piece of wood in half, and are fas-tened to the board exactly 10 inches apart,center to center. The center knife edge isa round piece of wood from which a pailis suspended by a cord. When the test pieces are seven or twen-ty-eight days old place them, still wet, onthe… … Fig. 2—Method of testing strength. and then slowly pour sand into it until theprism breaks. Carefully weigh thebucket with the cord and strip still at-tached. If the prism is not exactly oneinch square, correct the weight by dividingit by the product of its width times thesquare of its depth in…
