198 



M. R. Thalen on the Determination of 



5-foot bar it is a question of the permanent elongation here 

 necessary, or 0*025 Swedish decimal line — that is, in round 

 numbers, of 0*4 of the above-mentioned scale. 



Table I. 



Steel of medium hardness. A = 17*33 Swedish square 

 decimal lines. 



•No. 

 1 



P. 

 179 



AL. 



00 



No. 

 20 



P. 

 503 



AL. 



0-9 



No. 

 39 



I 



» 



AL. 

 12-2 



No. 

 57 



P. 

 469 



AL. 

 411 



No. 



P. 



AL. 



723 



75 



469 



68-6 



2 



238 



0-0 



21 



515 



1-0 



40 



734 



150 



58 



585 



41-2 



76 



585 



68-6 



3 



261 



00 



22 



526 



1-2 



41 



746 



17-8 



59 



700 



41-4 



77 



700 



68-7 



4 



284 



01 



23 



538 



1-3 



42 



757 



20-8 



60 



"757 



41-4 



78 



757 



68-9 



5 



307 



01 



24 



549 



1-4 



43 



769 



237 



61 



780 



41-5 



79 



792 



690 



6 



331 



01 



25 



561 



1-6 



44 



780 



267 



62 



792 



41-6 



80 



815 



691 



7 



353 



0-2 



26 



573 



1-6 



45 



792 



297 



63 



803 



41-8 



81 



838 



69-3 



8 



365 



0-2 



27 



585 



1-6 



46 



803 



32-7 



64 



815 



420 



82 



862 



69-5 



9 



377 



0-3 



28 



596 



1-9 



47 



8 



15 



35-6 



65 



826 



42-5 



83 



885 



698 



10 



388 



0-4 



29 



608 



2-2 



48 







371 



66 



838 



435 



84 



896 



70-3 



11 



399 



0-4 



30 



619 



2-4 



49 







38-4 



67 



850 



45-3 



85 



919 



715 



12 



411 



0-4 



31 



631 



2-7 



50 







39-1 



68 



862 



481 



86 



942 



74-5 



13 



423 



0-5 



32 



642 



31 



51 







39-7 



69 



885 



54-6 



87 



966 



80-5 



14 



434 



0-5 



33 



654 



3-7 



52 







40-2 



70 



907 



61-9 



88 



989 



89-7 



15 



446 



0-6 



34 



665 



4-4 



53 







40-6 



71 



930 



68-6 



89 



1012 



98-4 



16 



457 



06 



35 



677 



5-3 



54 







41-0 









90 



1035 



1070 



17 



18 



469 



480 



0-7 



0-8 



36 



37 



688 

 700 



6-4 



8-0 









72 

 73 



122 



68*6 



91 



1058 

 1081 



1178 

 128-5 



55 



238 



41-1 



238 



68-6 



92 



19 



492 



0-9 



38 



711 



9-9 



56 



353 



41-2 



74 



353 



68-6 



93 



1139 



156-8 



From the foregoing Table and the corresponding figure (fig. 1, 

 Plate III.), it is seen that after the loads were gradually raised to 

 815 pounds, the stretching-experiments began again with small 

 loads, which were then successively raised to 930 pounds, and 

 thereupon the same experiment was repeated. 



If for these three series the limit of elasticity is defined in 

 accordance with the definition given above, and taking as the 

 original length, 



In the first series L =500 decimal lines, 

 „ second „ =500 + 41*0 divisions, 



„, third „ =500 + 68*6, 



we get for the limit of elasticity the following approximate 

 values : — 



E x = 400, 



E 2 = 700, 



E 3 = 800. 



A number of similar examples might be adduced; but the fore- 



