OF ARTS AND SCIENCES. 79 



face and shape of the electrodes are likely to modify these values to a 

 certain extent. Thus the carbon electrodes used by Mr. Jones gave 

 the results shown in Tables XIV. and XV. The arrangement of the 

 electrodes was as already described, except that the anvil was sliglitly 

 inclined, and in the second series a weight of bent wire was added to 

 increase the normal pressure by a small amount. 



TABLE XIV. 



Electrodes, Carbon, Carbon. 



Mass in Grams Excursion of Hammer at Critical Point. 



In connection with the various preceding tables the following re- 

 sults obtained by Mr. Jones will be of interest. 



