but is injurious to the boiler.

It is no small matter to know just how to handle your dampers; don't
allow too much of an opening here. You will keep a much more even fire
by keeping the damper down, just allowing draught enough to allow free
combustion; more than this is a waste of heat.

Get all out of the coal you can, and save all you get. Learn the little
points that half the engineers never think of.

WOOD

You will find wood quite different in some respects, but the good points
you have learned will be useful now. Fire quick and often, but unlike
coal, you must keep your fire box full. Place your wood as loosely as
possible. I mean by this, place in all directions to allow the draft to
pass freely through it. Keep adding a couple sticks as fast as there is
room for it; don't disturb the under sticks. Use short wood and fire
close to the door. When firing with wood I would advise you to keep
your screen down. There is much more danger of setting fire with wood
than with coal.

If you are in a dangerous place, owing to the wind and the surroundings,
don't hesitate to state your fears to the man for whom you are
threshing. He is not supposed to know the danger as well as you, and
if, after your advice, he says go ahead, you have placed the
responsibility on him; but even after you have done this, it sometimes
shows a good head to refuse to fire with wood, especially when you are
required to fire with old rails, which is a common fuel in a timbered
country. While they make a hot fire in a firebox, they sometimes start
a hot one outside of it. It is part of your business to be as careful as
you can. What I mean is take reasonable precaution, in looking after
the screen in stack. If it burns out get a new one. With reasonable
diligence and care, you will never set anything on fire, while on the
other hand, a careless engineer may do quite a lot of damage.

There is fire about an engine, and you are provided with the proper
appliances to control it. See that you do it.

WHY GRATES BURN OUT

Grates burn through carelessness. You may as well make up your mind to
this at the start. You never saw grate bars burn out with a clean ash
box. They can only be burned by allowing the ashes to accumulate under
them till they exclude the air when the bars at once become red hot.
The first thing, they do is to warp, and if the ashes are not removed at
once, the grate bar will burn off. Carelessness is neg