ing down on them from the stoke-hold floor, as some stokers
quench their clinkers and ashes while they are up against the front of
the boiler, instead of drawing them forward a few inches from the front:
and as the pipe is out of sight under the plates of the floor, nobody
takes the trouble to lift them and examine--not only the pipe and the
cock, but that part of the boiler where the water streams down from the
drenched ashes so frequently. So there are disadvantages in both methods
of blowing out the boiler, and always will be, until the stoker learns
his business, and takes an interest in his work, not only for his own
sake, but his employer's also.

17. _Question._--What is the most important appendage to a steam boiler?

_Answer._--The safety-valve, but it is not always a safety-valve, when
it is weighted to twice the amount the boiler is certified to be worked
at safely. As an instance: Amongst the many engines employed at the
Midland Extension Works, St. Pancras, was a light steam crane for
hoisting earth from the deep excavations, there were in use small wooden
skips, and the pressure of steam was forty-five lb.; but after a time
there arrived large iron skips that the crane could not lift, even when
empty; there were about twenty men depending on the crane for their work
and the navvy-ganger was anxious for "something to be done," and the
crane man hinted about weighting the safety-valve, and no sooner said
than almost done; the safety spring balance was screwed down, and a
railway chair suspended from it by strong copper wire, and the steam
allowed to rise until it reached ninety lb. on the inch, and the big
iron skips were hoisted with their load of heavy ballast as easily as
the wooden ones had been. The boiler _happened_ to stand it.

18. _Question._--Have you any other instance?

_Answer._--Yes; in an establishment in Hammersmith some years ago, the
stoker was in the habit of putting a bit of iron on the end of the
horizontal lever of a safety valve when the steam rose too high, and the
manager was about, and when it went down he would take off the bit of
iron and put it where he could find it for the next occasion. The
manager had gone away one day, and advantage was taken of it to have a
little carouse in which most of the men took a part; and when the steam
rose the stoker popped his bit of iron on the lever and all was quiet
for a time, when another noisy safety-valve began to blow off, and on
w