APPARATUS FOR MEASURING STRAIN AND APPLYING STRESS. 



283 



Table VII. 



Diameter, 0"424". Length, 4"00". 12'8 divisions of scale = 1 min. of arc. 



Load in each 



Column I. 



Column II. 







Pan. 



No Tension. 



No Tension. 



Lbs. 







Reading. A 



Reading. A 



2 













157 



155 



3 



157 



155 





155 



157 



4 



312 



312 





157 



156 



5 



469 



468 





156 



157 



6 



625 



625 





156 



156 



7 



781 



781 





154 



156 



8 



935 



937 





155 



157 



9 



1090 



1094 





157 



157 



10 



1247 



1250 





156 



157 



11 



1403 



1407 





156 



157 



12 



1559 



157 



1564 



13 



1716 



156 





14 



1872 



157 





15 



2029 



159 





16 



2188 



168 





17 



2356 



120 





17-5 



2476 



950 





18 



3426 



400 





18-2 



3826 





18-5 



"Went off scale 





Column III. 



Load in each 



Tension 2400 lbs. 



Pan 





Lbs.' 







Reading. A 



2 









156 



3 



156 





155 



4 



311 





156 



5 



467 





157 



6 



624 





158 



7 



782 





156 



8 



938 





156 



9 



1094 





157 



10 



1251 





155 



11 



1406 





158 



12 



1564 





158 



13 



1722 





156 



14 



1878 





156 



15 



2034 





81 



15-5 



2115 





106 



16-0 



2221 





120 



16-5 



2341 





472 



17-0 



2813 



17-3 



Went off scale 



The results of Table VII. are plotted and are shown on fig. 25. 



3. Tension beyond the Elastic Limit. 



A machinery steel bar turned to a mean diameter of 0'537, with a length of 8*00 

 under test, was chosen. The bar was first placed in the torsion machine, and gave the 

 results under test shown by col. I., Table VIII. The mean twist for 75 inch pounds 



