And as this is our object, we want you to know it, and be benefitted by
the knowledge. Suppose you are on the road with your engine and load,
and you have a stretch of nice road. You are carrying a good head of
steam and running with lever back in the corner or lower notch. Now
your engine will travel along its regular speed, and say you run a mile
this way and fire twice in making it. You now ought to be able to turn
around and go back on the same road with one fire by simply hooking the
lever up as short as it will allow to do the work. Your engine will
make the same time with half the fuel and water, simply because you
utilize the expansive force of the steam instead of using the live steam
from boiler. A great many good engines are condemned and said to use
too much fuel, and all because the engineer takes no pains to utilize
the steam to the best advantage.

I have already advised you to carry a "high pressure;" by a high
pressure I mean any where from I00 to I25 lbs. I have done this
expecting you to use the steam expansively whenever possible, and the
expansive force of steam increases very rapidly after you have reached
70 lbs. Steam at 80 lbs. used expansively will do nine times the work
of steam at 25 lbs. Note the difference. Pressure 3 I-5 times greater.
Work performed, 9 times greater. I give you these facts trusting that
you will take advantage of them, and if your engine at I00 or I00 lbs.
will do your work cutting off at I/4, don't allow it to cut off at I/2.
If cutting off at I/2 will do the work, don't allow it to cut off at
3/4, and the result will be that you will do the work with the least
possible amount of fuel, and no one will have any reason to find fault
with you or your engine.

Now we have given you the three points which are absolutely necessary to
the successful handling of a traction engine, We went through it with