Hydro-oxygen Bloivpipe. 41 



reception. 



universal 



fulcrum, C, so that by means of a sliding weight at one end, the 

 platform and its appurtenances are counterpoised at the other. 

 The platform is kept in a horizontal position by the cannon ball, 

 supported in a sort of iron stirrup terminating in a ring, in which 

 the ball is placed. Upon the platform is situated an iron pan 

 with a handle, holding the brick, on a cavity in which as already 

 mentioned, the metal is supported. The apparatus being duly 

 prepared, and connected with the supply pipes, the hydrogen is 

 first allowed to escape, and then the oxygen, until the ignition 

 has attained apparently a maximum. The accomplishment of 

 this object may, of course, require the adjustment of either cock 

 several times, especially where there is any decline in the ' pres- 

 sure either of the one or the other gas in its appropriate reservoir. 



By means of the handles of the lever and of the pan, the ope- 

 rator is enabled to bring the metal into the position most favora- 

 ble for the influence of the heat, while his hands and face are 

 sufficiently remote to render the process supportable. In fusing 

 any quantity, not being more than four ounces, the platform may 

 be dispensed with, the handle of the pan being held in one hand 

 of the operator, while by the other, the cocks may be adjusted. 



When the blowpipe of fifteen jets, or any larger, may be em- 

 ployed, and the platform is necessarily resorted to, the cocks must 

 be adjusted by an assistant. 



Fig. 5 represents a cask made of boiler iron, three-sixteenths of 

 an inch thick, so as to resist an enormous pressure. The joints 

 are secured by riveting, as in constructing high pressure boilers. 



This cask communicates with the hydrant pipes, so called, by 

 which our city is supplied with water, of which the pressure va- 

 ries from a half to more than two atmospheres, say from seven to 

 thirty pounds per square inch, according to the number and bore 

 of the cocks from which the water may be flowing at the time, 

 for the consumption of the community. Hence, experiments, 

 while using this head, are best made towards bed-time, or be- 

 tween that time and sunrise. The vessel is filled with water 

 by opening a cock, F. on one side of the pipe, C, and allowing 

 the air to escape through the valve-cock, B. Being thus supplied, 

 the cock, F, closed, and a communication with a bell glass, into 

 which oxygen is proceeding from a generating apparatus, being 

 made by means of a flexible leaden tube, on opening the valve 

 cock, B, and the cock, E, the water will run out, and be replaced 



by gas from the bell. ' This process being continued till the iron 



cask is sufficiently supplied with gas, . . 



Whenever the eas is wanted for the supply of the blowpipe, it 

 is 

 cock 



only necessary to establish a communication between the valve- 



' ~\ and the upper gallows screw, fig. 3, of the cylinder, A, 



open the cock, F, so as to admit the water to press upon 



Secokd Series, Vol. IV, No. 10.— July, 1847. 6 



