408 



Messrs. W. Kellner and W. H. Deering. [Mar. 7, 



diameter, thus affording a check by varying area. For the 13- and 

 16-ton experiments, the 0'25-in. hole only was used, as the weights 

 required for the larger holes would have been unmanageable with the 

 means available at the time ; in this case, when damage to the mouth 

 of the hole in the stopper occurred by the blowing out of the gases, 

 the head of the stopper was only planed down. 



The amounts by which the weights were lightened in the last (and 

 usually in each) experiment of a series was the following : 



5 tons. 

 1 series. 



0'25-inch f 22 Ibs. 

 hole. 



0'35-inch f 

 hole. 1 



5 tons. 

 1 series. 



56 Ibs. 

 = 0-26 ton 



5 tons. 6 tons. 



1 series. 4 series. 



0'40-inch f 56 Ibs. 28 Ibs. 



hole. \ = 0'2 ton = O'l ton per sq. inch. 



The weight- differences are, of course, calculated into tons per 

 square inch on the measured areas of the holes, the diameters of 

 which differed slightly from 0*25 in., &c. As mentioned above, half 

 the weight-difference (the mean of the last two experiments of a 

 series) is taken for the end result. 



The following were the results obtained : 



