54 



MR. LEONARD BAIRSTOW ON THE ELASTIC LIMITS OF 



axle steel under the same conditions, the elastic range determined by test and 

 recovery agreeing very closely with that found by repetitions of stress. On the other 

 hand, the Bessemer steel showed an elastic range 33 per cent, greater than that which 

 could be maintained against repetitions. Possibly a more sensitive extensometer, or a 

 longer specimen, would have yielded results in accordance with the earlier materials, 

 but no means of testing this were available. Until further experiments have been 

 made, this method of finding the elastic ranges by producing fatigue and recovery is 

 uncertain. *** 



Specimen No. 7 of the axle steel seems to indicate the possibility that the great 

 deformations produced during rolling cause the high primitive elastic limits which are 

 always found in bars of iron and steel. 



In conclusion the author wishes to express his great indebtedness to Dr. STANTON 

 for his interest and help, and for the opportunity of carrying out a research which he 

 had proposed and commenced. He also begs to thank Dr. GLAZEBROOK, F.R.S., for 

 the interest which he has shown in the work, and for the means of carrying on the 

 experiments. 



TABLE I. Tensile Tests of the Materials Used. 



TABLE II. -Analyses of the Materials Used. 



