42 Hydro-oxygen Blowpipe. 



the gas, the efflux being regulated by B, or preferable by a cock 



of the ordinary construction, one of which kind should be inter- 

 posed at a convenient position between the valve-cock, B, and 

 cylinder, A. 



T, represents a glass tube, which, by due communication with 

 the interior, shews the height of the water, and consequently the 

 quantity of gas in the vessel. 



G, H, represents a gauging apparatus, consisting of a cast iron 

 flask, of about a half a pint in content, and a glass tube of about 

 a quarter of an inch in bore, which should be at least five feet in 

 height. The tube is secured air-tight into the neck of the flask, 

 so as to reach nearly to the bottom within* The flask is nearly 

 full of mercury. Under these circumstances, when a communica- 

 tion is made, by a leaden pipe between the cavity of the flask and 

 that of the reservoir, an equilibrium of presure resulting, the extent 

 of the pressure is indicated by the rise of the mercury in the tube. 



In order to generate hydrogen for the supply of a reservoir like 

 that represented by the preceding figure, I have employed the 

 vessel represented by fig. 7. This vessel, by means of a suitable 

 aperture, susceptible of being closed by a screw plug, is half fill- 

 ed with diluted sulphuric acid. Being furnished with a tray of 

 sheet coper, D, punctured like a coal "sieve, and supported by a 

 copper sliding rod, E, strips of zinc are introduced in quantity 

 equal to the capacity of the tray. The sliding rod passes through 

 a stuffing-box, F, at top of the reservoir, so that the operator may, 

 by lowering or raising the tray, regulate or suspend the reaction 

 between the zinc and its solvent, accordingly as the supply of 

 hydrogen is to be produced, suspended, increased, or diminished. 



The communication with the reservoir is open and regulated 

 by means of a cock, P, furnished with a gallows screw, G, for 

 the attachment of a leaden pipe, as above described, in the pro- 

 cess for supplying the reservoir with oxygen. 



Another apparatus for producing a supply of hydrogen, is rep 

 resented in fig. 6. It consists of two similar vessels of boiler 

 iron, each capable of holding forty gallons. They are lined in- 

 ternally with copper, being situated upon a wooden frame, so that 

 the bottom of one is two-thirds as high as the top of the other. 

 The upper portions of these vessels communicate by a leaden 

 pipe. B, of about half an inch bore, furnished with a cock, while 



of one and a half inches. 



upper 



another 



mounted by a globular copper vessel, of 

 about twelve inches in diameter, which, from its construction, 

 renders it possible to introduce an additional supply of concen- 

 trated aeid, while the apparatus is in operation, without reducing 

 the pressure within the reservoir, by permitting the excess above 

 the pressure of the atmosphere to escape. This object is accom- 

 plished as follows : 



