274 



CEMENTS, LIMES, AND PLASTERS. 



234 



AGE IN MONTHS 



FIG. 62.* Tensile tests, Sault Ste. Marie. 



Compressive strength. Tests on various natural cements carried 

 out by Clifford Richardson f are summarized in Table 131. 



TABLE 131. 

 COMPRESSIVE TESTS OP NATURAL CEMENTS. (RICHARDSON.) 



The following tests (Table 132) of compressive strength were made on 

 4-inch cubes at the Watertown Arsenal .J 



* From Johnson's "Materials of Construction", p. 571. 



t Brickbuilder, vol. 6, p. 253. 



Report on tests of metals, etc., at Watertown Arsenal for 1902, pp. 377-381. 



