101 FUSION OF STRONTITES, &C. 



sed until it becomes so ; and the tub should be furnished with 

 shelves at the usual height, to support the jars. Having sub- 

 jected the gas in the cells to sufficient pressure, the velocity of 

 efflux must be regulated by opening the cocks more or less. 

 For this purpose, the perforations in the keys should be narrow 

 and oblong ; so as to admit of a gradual increase, or diminu- 

 tion, of the quantity of gas emitted. 



The compound blowpipe represented by Fig. ii, consists of 

 two common brass blowpipes whose points are made to meet 

 in a perforation in the conical frustum of\ silver a. Now if 

 the orifices b, c, of these pipes, be inserted into themouths 

 I, I, of the pipes of delivery, it is obvious, that on open- 

 ing the cocks H, H, any gases contained in the cells from 

 whence these pipes issue, will be forced through them by the 

 pressure of the water in the tub, and will meet in a point within 

 the frustum. When the hydrogen and oxygen gases are thus 

 made to meet, and are ignited, that intense heat is produced, 

 by means of which I was enabled to accomplish the fusions, 

 mentioned in a former part of this paper. But all this is fully 

 explained in my memoir, to which I have so frequently re- 

 ferred, in the course of this communication. 



It seems not improper to subjoin, that when the frustum of 

 the compound blowpipe a, Fig. 2, is inserted into a receiver, and 

 a supply of the hydrogen and oxygen gases is supported by 

 means of the hydrostatic blowpipe, or the apparatus described 

 in this paper, very convenient means are aliorded of recom- 

 posing water — an operation of so much importance to modern 

 chemical theory, that it can never become obsolete, or un- 

 interesting to the cultivators of science. r lhe advantage of 

 the method consists in this, that the gases mix in the frus- 

 tum before they become ignited, and must enter into the re- 

 ceiver in a state of combustion. This therefore is not depen- 

 dent on the quantity of azot, or other noxious gas collected 

 in the vessel ; and as the burning gases may be made to enter 

 under the pressure of a considerable column of water, the im- 

 pure air, collected during the process, may be forced out 

 through a tube into a mercurial apparatus; the operation may 

 Continue as long as desired, and the proceeds may be examin- 



