fteen pounds on the jet steam
gauge if coal is coarse, or ten pounds if coal is small. Next, the
driving engine steam valve should be opened wide and the throttle valve
opened just enough to supply the proper amount of coal to the fire-box.

8. Q. How is the distribution of coal over the grate area accomplished?

A. By means of a low-pressure constant steam jet located in the back and
bottom portion of each distributor elbow, as indicated by its
individual pointer on steam gauge.

9. Q. By increasing the jet pressure, will more coal be carried to
forward end of fire-box and against the flue-sheet?

A. Yes, it will, and by decreasing the jet pressure more coal will be
fed at middle and back end of fire-box.

[Illustration]

10. Q. Can the fireman direct the even distribution of coal in the
fire-box?

A. Yes; by changing position of the dividing rib located in the transfer
hopper, and by moving the regulating lever to either side.

11. Q. Should the sliding plates at the bottom of the tank be closed
before coal is put on tank?

A. Yes, so that screw conveyor will not become clogged and inoperative.
Only one slide should be opened at a time and coal fed from tank as
required.

12. Q. In case the stoker becomes clogged or it is desired to reverse it
for any reason, what must be done?

A. The operating rod located on the back-head of the locomotive
boiler--if the piston is making a power stroke--should be moved to its
lower position, and if the piston is making a return stroke, it should
be moved to its upper position. This moves a small valve in the
auxiliary head, bolted to reverse head, and steam is admitted to
opposite head of cylinder, causing the piston to change its direction.
The return of the operating rod handle to a central position causes the
driving engine to resume its normal operation.

13. Q. How can the fireman observe the condition of fire in fire-box?

A. The elbows are provided with peep valves with swinging covers through
which the coal supply and condition of fire may be seen.

14. Q. Why are two gauges necessary?

[Illustration]

A. The driving engine gauge on the left indicates the pressure of steam
used by the driving engine. The one on the right has two indicators, the
red indicator showing the steam pressure on the jet in left elbow, and
the black indicator showing the pressure on the jet in the right elbow.

15. Q. When train is standing on siding for a short period, what shou