ROUGH-AND-TUMBLE ENGINEEJ 67 



injury to the boiler, in case of an accident or when, by 

 some means, you might be deceived in your gauge of 

 r, if by mistake, a fire was started without much 

 water in the boiler. 



Should the plug melt out, it is necessary to replace it 

 at once, or as soon as the heat will permit you to do so. 

 ght be a saving of time to have an extra plug always 

 ready, then all you have to do is to remove the melted 

 one by unscrewing it from the crown sheet and screwing 

 the extra one in. But if you have no extra plug you must 

 remove the first one and refill it with babbitt. You can 

 do t! ling one end of the plug with wet clay and 



pouring the metal into the other end, and then pound- 

 ing it down smooth to prevent any leaking. This done, 

 you can screw the plug back into its place, 



If you should have two plugs, as soon as you have 

 im-lted out one replace it with the new one, and refill the 

 - at your earliest convenience. By the time you have 

 replaced a fusible plug a few times in a hot boiler you 

 will conclude it is better to keep water over your crown 

 sheet. 



LEAKY FLUES 



What makes flues leak? I asked this question once, 

 and the answer was that the flues were not large enough 

 to fill up the hole in the flue sheet. This struck me 



