INNER BASES------15-POUNDER GUN MOUNTS.	147;
No. 7221.
Marks, !if 15
Diameter, ".505.
Sectional area, .20 square inch. Gauged length, 2".
Applied loads per square inch.	Elongation per inch.	Successive elongation per inch.	Permanent set.	Successive permanent set.	Remarks.
Pounds.	Inch.	Inch.	Inch.		
1,000	0.	0.	0.	0.	Initial load.
5,000	.00010	.00010	■ 0.	0.	
10,000	. 00030	. 00020			
20,000	.00060	. 00030			
30,000	.00100	.00040			
32,000	.00110	.00010			
33,000	.00115	.00005			Elastic limit.
34, t}00	. 00850	.00735			
35,000	.00925	.00075			
36,000	. 01005	.00080			
37,000	. 01095	.00090			
38,000	.01175	. 00080			
73,950					
		1			
......................pounds.. 73,950
..........................do... 33,000
.........................inch.. .1650
..........................do... .00115
..........................do...	.045
............................... 16.9
....................... ".70 from neck
granular 80 per cent, silky 20 per cent
15.״ ,*18.״ ...........................
General summary.
Tensile strength per square inch of original section.........
Elastic limit per square inch of original section............
Elongation per inch after rupture............................
Elongation per inch under strain at elastic limit...
Reduction in diameter at point of rupture....................
Reduction in area after rupture, per cent of original section
Position of rupture..........................................
Character of broken surface..................... . . . . . ..
E ־׳*ngation of inch sections...................... . ........
No. 7222.
Marks, fins Diameter, ".505.
Sectional area, .20 square inch. Gauged length, 2".
Applied loads per square inch.	Elongation per inch.	Successive elongation per inch.	Permanent set.	Successive permanent set.	Remarks.
Pounds.	Inch.	Inch.	Inch.		
1,000	0.	0.	0.	0.	
5,000	.00015	.00015	0.	0.	
10,000	.00035	.00020			
20,000	.00070	. 00035			
25,000	.00100	.00030			
29,000	.00120	.00020			
30,000	.00125	.00005			Elastic limit.
31,000	.00630	. 00505			
32,000	.00700	. 00070			
33,000	.00755	.00055			
34,000	. OO^ö	.00040			
35,000	.00865	. 000^0			
36,000	.00950	.00085			
74,500						Tensile strength.
.....................pounds..	74,500
........................do...	30,000
......................inch..	.1400
........................do...	.00125
........................do...	.045
*............................ 16.9
..................... ".28 from neck
granular, silky spot at circumference .......................... ".13, ".15*
General summary.
Tensile strength per square inch of original section...
Elastic limit per square inch of original section......
Elongation per inch after rupture......................
Elongation per inch under strain at elastic limit......
Reduction in diameter at point of rupture..............
Reduction in area after rupture, per cent of original section..
Position ol rupture....................................
Character of broken surface.....................
Elongation of inch sections..................