436 Mr. Herapath on True Temper attire, and the [Dec. 



its constants to be a little changed to accommodate its results to 

 the new temperatures. 



By Table 4th 250° require a correction of — -9°. 



Therefore 250-0° 

 —9 



249-1 which gives Tab.3dT= 1205-1 log.3-0810231 



a* = 7-4445621 



3-3542 0-5255852 

 2-2637 



1-0905 log. 0-0376257 . . A 



A x 8=0-3010056 



A x -2= -0075251 



b = 1-4771213 



61-05 1-7856520 



The theoretical tension is, therefore, 61-05 in. By Dr. Ure's 

 experiments, it is 61-90, by Mr. Southern's 60-00, and by Dr. 

 Ure's formula, it is about 62-95. 



Exa?nple 4. — It is required to calculate the tension at 295° 

 Fahr. mercurial. 



295° 

 Cor. Tab. 4, -2-1 



292-9, hence Tab. 3, T = 1242-4 log. 3-0942014 



a = 7-4445621 



3-4580 0-5388235 

 2-2637 



1-1943 -0771134.. A 



A x 8 = -6169072 



A x -2 = -0154227 



b = 1-4771213 



128-66 2-1094512 



The tension by theory is, therefore, 128-66. By Dr. Ure's 

 experiments, it is 129. 



* To aroid repetitions, I shall hencciorward designate the logarithms of the constant 

 .jiiantitics -002783313 and 30 by a air 1 b. 



