102 ■ FUSION OF STRONTITES 



the rest be open. Then let as much water be poured into the 

 tub, as will rise half an inch above the surface of the chests, 

 and fill all the jars of the apparatus. The two air-cells 

 whose cocks remained open, will now be filled with water, 

 because the air had liberty to pass out of them: but the air- 

 cell behind the partition K K, will remain empty of water, 

 because, as its cock was closed, the air was confined, and the 

 entrance of the water thereby prevented. The air-cell thus 

 unoccupied by water, for the sake of distinction, I term the 

 regulator; the propriety of which will be seen presently. 



In operating with the common pneumatic tub, as the large 

 jars and air-holders become tilled with gas, it is necessary to 

 Jade out of the tub, the water displaced from them, as it 

 would otherwise rise so high, as to overflow; and to float, 

 and overturn the jars, no longer holding water. But in 

 this new apparatus, this inconvenience is avoided, by al- 

 lowing an escape of air from the regulator, adequate to 

 the descent of water from the jars. For as this air, is necessa- 

 rily subjected to hydrostatic pressure ; it will escape if the 

 cock a be opened, and a proportionate quantity of water, 

 will subside into the regulator. When the jars and air- 

 holders, are again filled with water, there would be a defici- 

 ency of this fluid, were not that which had been allowed 

 to subside into the regulator, again expelled therefrom, by 

 the action of the bellows at D. By the extension of 

 these bellows, which is effected by means of their handle and 

 rod, the valve of the pipe of emission at k, shuts; that of the 

 suction-pipe at e, opens, and the air enters the bellows. The 

 hand being removed from the handle, the lead on the top 

 of the bellows depresses them ; and the air within being com- 

 pressed, shuts the valve of the suction-pipe, opens that of the 

 pipe of emission at k, and enters the regulator, from which 

 it expels a quantity of water equal to the bulk which the 

 bellows gained by extension: and as all this is repeated at 

 every stroke of the handle, it follows, that the water which 

 had been allowed to subside into the regulator, may be quickly 

 expelled therefrom. 



