178 SOLDERINa APPARATUS. 



ders easily without injuring the surface of the 

 metal soldered. The bowl at the top is intended 

 to be used as a reservoir while the blowpipe is in 

 use, the heat from below making the water in it 

 so hot, that when emptied into the boiler, by 

 turning the stopcock, it immediately gives off 

 steam, and prevents any loss of time. The boiler 

 would not require replenishing more than once an 

 hour, or perhaps not so often, as it would of course 

 depend upon the power employed. 



This method of replenishing will be found much 

 better than any self-acting arrangement, being 

 incapable of derangement. 



As a matter of necessity, a little experience is 

 required to develop its powers ; but I venture to 

 express the confident belief that it will save a 

 great amount of time when worked against any 

 other form of blowpipe. (See Fig. 19.) 



Another apparatus of mine is for melting down 

 gold or silver in crucibles, by the action of a 

 stream of air blown into a gas flame, and directed 

 upon the bottom of the crucible. This is an 

 exceedingly valuable apparatus for melting down 

 scraps and alloying-metals. 



Another is the application of a series of power- 

 ful Bunsen's burners to melt the softer metals in 

 large quantities (as shown in action), capable 

 of melting a quarter of a cwt. of lead in fifteen 

 minutes. 



I have also a Bunsen's burner, to which I have 



