WOKK DONE ON BARS 249 



This has been done, it will be at once apparent, by taking 

 away the inches 8 and 9 to which the local extension is 

 onfined and reckoning the work on the remaining eight. 

 Measuring the area of the diagram A I F E D with the 

 planimeter, it is found to contain 14 - 14 square inches. 

 Dealing with this as before, it is found that the work per- 

 formed per cubic inch is 



14-14 _2_ 



= 10 x 0788 x 3 



= 5 '98 inch-tons. 



This agrees very well with the result obtained by the 

 approximate formula. 



