462 METALLURGY OF CAST IRON'. large mass and cooled very slowly it is not surprising that the fracture shows the iron in the mortar body to be much softer (or open-grained) than that in the test bars from the base ring. The tensile strength of the two specimens taken for acceptance of the 12-inch return mortar or lower base casting as above described was as follows: No. r . . . 37,100 Ibs. No. 2 ... 37,000 Ibs. TAHI.K 91.—TRANSVKKSK. TKSTS (>F < \\K-\VH KI-'.I. IK<»N. 1 . I 6 ! Common rule measurement. Mierom't'r' »)r.j] .... Broke at measure- *Hmi " *n ment. i "°"' pounds. Strength per square inch in pounds. Rou^h bars. 19 I J4 in. s<]uare......... ;Roug'h bars 22 i in. s<juarc ...... ..... HIJ in ,c"s its. .','s \\ •» \"f\ Rough bars. i,# in. duun ..... ..... IK fit in. ,i 1 1 in. 2 ;,.j«> ''^ :••••:•. ^ 36 27 J:'-";5 ::::;• Turned bur. Test bars furnished 1»v A. Whitney Kt Suns, I'hilmirlphia. l'»i. Trnlr*! by John R. Matlock, Jr., at the works of Kichlr Bros.' Tenting MavhineCo., rhilu-delphia, Fa,, June 27th, iH.^. Witness. W. C, Cutler. In the chill roll iron, Table 90, pag'c 461, a few of the pieces were selected after having been broken for transverse strength and pulled for the tensile strength. Bar Xo. 15 pulled 6,100 pounds; Nu. 16 pulled 23,700 pounds: and Xo. 17 pulled 30,100 pounds. The iron in the half-inch bars showed a white erystal-line fraeture, likewise the one-inch square. The one and one-eighth inch diameter rough bars showed a very close knit grain tending to a light color. The one and one-eighth inch turned bars are also very closeTested by Thomas D. West, at the works of the T. D. West Foundry Co , Sharpsville, Pa., Sept. i8th, 1894. Witnesses, Geo. H. Boyd andG. M. Mcllvain.