612	CONCRETE CUBES■.
Compressive tests of concrete cubes—Continued.
Marks.	Composition.				Age.	Dimensions.			Sectional area.	Weight, total.	Weight per cubic foot.	First crack.	Ultimate strength.	
	Ce- ment.	Sand.	Gravel.	Stone.		Height.	Compressed surface.						Total.	Per square inch.
								Inches.	Sq. inches.	Ibs. ozs.	Pounds.	Pounds.	Pounds.	Pounds.
	1	2£	8			do		12.12	12.14	12.04	146.17	154 12	150.94	187,400	189,500	1,300
	1	2*	8			do		12.12	12.13	12.05	146.17	155 8	15]. 68	228,600		1,560
	1	2¿	8			do		12.10	12.13	12.14	147.26	153 4	148. 62	218,500	259,100	
				4		12.02	12.10	12.23	147.98			375,000	443,000	2,994
				4		12.11	12.21	12.09	147.62			295,000	351,000	2,378
				4		12.12	12.16	12.24	148.84			347,000	503,000	3,379
				7»		12.16	12.09	12.22	147.74			261,000	289,000	1,956
				7i		12.25	12.24	12.07	147.74			265,000	312,000	2,112
				7i		12.17	12.10	12.21	147.74			301,000	319,000	2,159
No. 3										148.60			319-, 000	321,000	2,160
						12.01	12.07	12.19	147.13			281,000	286,500	1,947
						12.33	12.22	12.07	147.50			295,000	321,000	2,176
								12.16	148.60				255,700	1,721
						12.19	12.20	12.07	147.25				269,500	1,830
						12.09	12.07	12.21	147.37				268,900	1,825
						12.20	12.02	12.23	147.00				235,300	1,601
						12.19	12.08	12.03	145.32				210,100	1,446
						12.05	12.22	12.16	148.60				192,800	1,297