out he is delayed a couple of hours, at least, before he can put in a
new plug and get up steam again. Now suppose he had not had a soft plug
(as they are sometimes called). He would have stopped before he had low
water. He would not even have had a hot crown sheet, and would only
have lost the time he waited on the tank. This is not a fancied
circumstance by any means, for it happens every day. The engineer
running an engine with a safety plug seldom stops for a load of water
until he blows out the plug. It frequently happens that a fusible plug
becomes corroded to such an extent that it will stand a heat sufficient
to burn the iron. This is my greatest objection to it. The engineer
continues to rely on it for safety, the same as if it were in perfect
order, and the ultimate result is he burns or cracks his crown sheet. I
have already stated that I have no objection to the plug, if the
engineer did not know it was there, so if you must use one, attend to
it, and every time you clean your boiler scrape the upper or water end
of the plug with a knife, and be careful to remove any corrosive matter
that may have collected on it, and then treat your boiler exactly as
though there was no such a thing as a safety plug in it. A safety plug
was not designed to let you run with any lower gauge of water. It is
placed there to prevent injury to the boiler, in case of an accident or
when, by some means, you might be deceived in your gauge of water, or if
by mistake, a fire was started without any 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. It might 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 this by filling one end of
the plug with wet clay and pouring the metal into the other end, and