WROUGHT IRON.
440
No. 7436.
Burden’s Best Iron. Diameter, 1".129.
Sectional area, 1 square inch. Gauged length, 10".
Applied loads per square inch.	In gauged length.		
	Elonga- tion.	Set.	Remarks.
Pounds. 1,000 5,000 10,000	Inches. 0. .0012 .0030	Inch. 0. 0.	
20,000 26,000 26,500	.0067 .0090	0.	
	.0094		
27,000	.0098		Elastic limit. Load sustained 2 minutes, then rapid elongation occurred and load fell.
	/ .0233		
24,800	1 .0242		
25,000	.0256		
25,500	.0272		
26,000	.0335		
26,500	.0420		
27,000	.0820		
	/ . 0890		
25,500	\ . 0990		
26,000	.1070		
26,500	.1230		
27; 000 27,500 28,000	.1381		
	.1420		
	.1472		
29,000	.1735		
30.000 Rested v 1,000 5,000 10.000	.1980 without load 0. .0008 .0023	.1857 50 days. 0. 0.	
20;000 30.000 34.000 35.000 35.000	.0054 .0084 .0096	0. 0.	!Micrometer reset at zero on 8" of the original gauged length.
	.0105 .0107	.0005	Second application of load.
35,400 36.000 38.000 40.000 42.000 44.000	.0526		
	.28		
	.36		
	.42		
	.49		
	.59		
46', 000 48,000 49,900	.73		
	.95		
	1.57		Tensile strength. =25 per cent.
0	2.50		
			
Elongation of inch sections: ".18, ".19, ".20, ".21, ".23, ".25, "56*, ".31, ".21, ".16.
• Diameter at fracture, ".85; area, .567 square inch.
Contraction of area, 43.3 per cent.
Appearance of fracture, fibrous.