and run in;
use live steam in low-pressure cylinder only, for the broken piston.
With broken cylinder head, would cover ports on that side. Open separate
exhaust and run in with low-pressure side. Would not take down main rod,
but would take out pop valves in both cylinder heads and see that the
cylinder is properly oiled. For low-pressure head broken, would cover
ports on that side, open separate exhaust valve and use high-pressure
side; need not take down main rod, but would see that the cylinder is
well oiled.

21. Q. In the event of separate exhaust valves failing to work when
throttle is wide open, what can be done to assist in opening?

A. Ease throttle off very fine to reduce the receiver pressure; in a
moment or two the separate exhaust valve should then move. If this did
not work, would shut off entirely, even at the risk of stalling, as in
that event the train could be started again with engine cut in simple.

22. Q. If a transmission bar on a cross compound is broken, what would
you do for the right side? For the left side?

A. For right side would cover ports on that side, take out pop from
cylinder head, open separate exhaust and run in with other cylinder. For
left side, cover ports and fasten valve stem same as for right side.
Would leave main rods up, keep separate exhaust open in both cases and
see that cylinder is well oiled.

23. Q. In the event of a cross compound beginning to jerk badly and
cylinder head pops in low-pressure cylinder popping, where would you
look for the trouble?

A. That either the high-pressure valve or piston packing was blowing
live steam into the receiver and then into low-pressure steam chest. If
possible would locate trouble and report accordingly.

24. Q. If during a trip you found the piston valve rings of a cross
compound were broken, what would you do?

A. If nothing but rings were broken, would reduce boiler pressure about
25 per cent. and go on with my train if possible.

25. Q. If piston valve on cross compound was broken so it became
necessary to remove it, what should you do?

A. Remove the broken piston valve, reduce boiler pressure to 100 pounds
and proceed.

26. Q. What is the difference between a Vauclain four-cylinder compound,
a four-cylinder tandem, a balanced and a Mallet compound in their
arrangement of cylinders?

A. A Vauclain compound has two cylinders on each side, one above the
other, and both piston rods connected to one cross-head. A f