THE BOOK OF THE LANTERX. 81 



be not taken, the sudden influx of oxygen to the burner, 

 when the dissolving lever is turned, will almost infallibly 

 cause the flame to snap out with a sharp crack. 



The mixed jet is as easily worked as the safety form and 

 despite the confidence-inspiring name of the latter is, 

 in my opinion, quite as safe in careful hands. In some 

 forms of mixed jets pumice-stone chambers, receptacles 

 charged with discs of wire-gauze, and other arrangements 

 which are supposed to prevent the flame passing back 

 through the tubes, form part of the design. I look upon 

 such contrivances as mere obstacles to the free passage of 

 the gas \ and, although some of my jets were originally 

 provided with them, I did away with them as quickly as 

 possible. 



The dissolver for a triple lantern is naturally more com- 

 plicated ; but taps have been devised which are so arranged 



FIG. 33. 



that any one of the three lanterns can be put in or out of 

 action at will. Such a tap is shown at fig. 33. Another 



G 



