ON THE MECHANICAL PKOPERTIES OF STEEL. 



135 



Exp. TII. — Bar of Steel from the Barrow Haematite Steel and Iron Company. 



Mark on bar, "H:4+," 



Before experiment. After experiment. 



Height of specimen -974 inch. .... -581 inch. 



Diameter of specimen .... •12 inch. .... l-Ol inch. 



Area of specimen -4071 sq. in. .... •8011 sq. in. 



No. 



of 



Exp. 



Weight laid 



on 

 specimen. 



Weight laid 



on per square inch 



of section. 



Com- 

 pression, 

 in inches. 



Remarks. 



1 

 2 

 3 



4 

 5 

 6 



7 

 8 

 9 



lbs. 

 37438 

 44966 

 52166 

 58950 

 66022 

 73134 

 80214 

 88134 

 91840 



tons. 

 16-713 

 20'074 

 23-288 

 26-316 

 29-474 

 32-649 

 35-809 

 39-345 

 41-000 



lbs. 



91951 

 110440 

 128124 

 144786 

 162156 

 179722 

 197023 

 216465 

 225568 



tons. 

 41-049 

 49-303 

 57-198 

 64-637 

 72-391 

 80-233 

 87-952 

 96-636 

 100-700 



-075 

 •100 

 •133 

 -190 

 -225 

 •295 

 •325 

 •375 

 •392 



No cracks. 



Results. — Here the strain per square inch(Pj)causingrupture is 225,568 lbs., 

 or 100^7 tons, and the corresponding compression ^^Z^) per imit of length 

 is -392. By formula (13). — The work (m) expended in producing rupture 

 = 44211. 



Exp. VIII. — Bar of Steel from the Barrow Haematite Steel and Iron Company. 



Mark on bar, "H5 + ." 



Before experiment. 



Height of specimen -968 inch. 



Diameter of specimen .... ^72 inch. 

 Area of specimen ^4071 sq. in. 



After experiment. 

 •58 inch. 

 •996 inch. 

 •7791 sq. in. 



37438 

 44966 

 52166 

 58950 

 66022 

 73134 

 80214 

 88134 

 91840 



16^713 



20^074 

 23-288 

 26-316 

 29-474 

 32^649 

 35^809 

 39^345 

 41-000 



91951 

 110440 

 128124 

 144786 

 162156 

 179722 

 197023 

 216465 

 225568 



41-049 

 49^303 

 57^198 

 64-637 

 72-391 

 80-233 

 87-952 

 96-636 

 100-700 



•087 

 •100 

 •1.37 

 -190 

 •233 

 -288 

 -325 

 •375 

 •400 



Wo cracks. 



Results. — Here the strain per square inch(Pj)causiugrupture is225,568 lbs., 

 or 100-7 tons, and the corresponding compression (ZJ per unit of length 

 is -4. By formula (13). — The work (m) expended in producing rupture 

 = 45113. 



