234 Mr. J. P. Joule on the Effects oj Magnetism^ Sfc. 

 Experiment 17. Same wire. Tension 1680 lbs. 



The uniformity of the numbers contained in the last column 

 of each of the two preceding tables affords conclusive evidence 

 of the correctness of the law I have stated, viz. that in the case 

 of tension the shortening effect is proportional to the current 

 traversing the coil mnltiplied by the viagnetic intensity of the 

 bar. 



In order to discover, if possible, what proportion the short- 

 ening effect bears to the force of tension, I have constructed 

 the following table from the results observed with currents of 

 about 700 and 1000 intensity in the preceding experiments. 



With the exception of the number 80, the results of the 

 last column of the above table agree sufficiently well together 



J^ 



