 | Engineers Seat - On the right hand side of the locomotive when facing out
the front of the cab. See photo
on Backhead Detail page showing Bill Thomas in this position. Both
engineer and fireman seats were fold up seats. |
| Fireman's Seat - On the left side of the locomotive when facing out the
front of the cab. As second photo
on the Backhead Detail page shows the fireman in this position. Note
the placement of the oil burner controls to the right of the fireman. |
| Burner Vent & Controls - Shows vents on front of the drum admitting
air to the oil burners. Earlier Backhead
drawing on the Backhead Detail page also shows openings on side of
drum. It is likely there were holes in both locations as this was the
only air supply to the oil burners. Later
photos of NPC No 21 show that the headlight was moved up and a hole was
placed in the front of No 21 supplying air through a cowling to the drum
openings. The two levers on the drawing operate the dampers -
controlling the extent to which the front and side openings admit air. |
| Oil Burner Controls - These controls which face the fireman control the
flow of oil to the burners. A side view of these controls is clearly
shown on the photo
of the firemen on the Backhead Detail page. A schematic
of these controls is also shown on the Backhead Detail page. |
| Air Brake Stands - While only one is shown, there were probably two brake
stands, the direct air engine brake stand and the automatic air train brake stands. They were likely cleated
off the cab walls. They would have been cleated to the front cab wall
or to the side wall to the side of the engineer. We feel the front cab
wall is the more likely location. The Backhead Detail page shows a Westinghouse
Brake photo on the left and an engine
brake photo on the right. Note that brake gauges would have
been placed in front of the engineer on the front cab wall. |
| Lifting Feedwater Injectors - Mounted on the upper slope of the
boiler sides. The injectors were probably “lever action” as was
common locomotive practice. The water and steam settings were pre-set and
the engineman pulled the lever to start the feed. A photo
on the Backhead Details page shows a feedwater injector just behind Bill
Thomas' head. |
| Johnson Bar - Is secured to the floor to the left of the engineer's
seat. |
| Hydrostatic Lubricator - Two are shown, one on each side of the
backhead. They would have been similar in design to the photo
on the Backhead Detail page. Globe valves shown would allow steam to
be shut off from the lubricators in case of breakage and when the
lubricators were to be filled with steam oil. Oil is fed to the
cylinders via a line going to the cylinder covers. |
| Dual Water Glasses - This is not obvious from the photo but it is likely
they were positioned 2 feet in front of the backhead so as to be visible to
the engineer and fireman by looking sideways. Note that given the
slant of the boiler, it was not necessary that the cab side of the steam
drum contain water. As a result, the upper and lower ends of the water
glasses in all likelihood extended from just below the top of the boiler to
the lower part of the steam drum. The only reason the water glasses
would extend higher on the steam drum would be to check whether water was
too high, causing a risk of priming the engine's cylinders with water.
Lines feeding the water tubes would be braced with brackets attached to the
boiler or possibly the top of the cab. Globe valves at the top and
bottom of the water glasses would allow the water to be shut off in the
event of breakage of the glass. Globe valves would also be placed
there the pipes exited the boiler and steam cylinder so the flow should be
shut off in the event of pipe breakage. The preferred water level on
this engine is 2 inches above the inner corrugated drum casing. This
keeps spots in the boiler from overheating. Too much water in the
steam drum reduces the steam generating capacity of the engine. |
| Oil Lamps - Lamps with vertical slits would be mounted to throw light on
the water glasses. They are shown to the inside of the glasses in the
drawing. The drawing shows them fixed to the pipe work and off straps
attached to the backhead. |
| Turret - Comes off the middle of the steam drum backhead. It
supplies steam to the two hydrostatic lubricators, the compressor lubricator
and the oil injector. |
| Throttle Valve - Was at the junction of the dry tubes. It controlled
the flow of steam to the cylinders. |
| Throttle - Earlier drawings
on the Backhead Detail page show the throttle swinging directly off the
throttle valve. To reach the throttle, the engineer would need to
reach behind his head and around the steam pipe. In practice, the
throttle would have been in front of the engineer's seat in front of the
Johnson bar. The above drawing assumes it was suspended from the
ceiling with a linkage back to the throttle valve. |
| Compressor Lubricator - Shown on the left side of the backhead, this
lubricator uses steam pressure to feed oil to the air compressor mounted on
that side of the engine. While shown above the entry door (for
clarity) it would have been mounted to the right of the entry door behind
the throttle. |
| Steam Dry Lines to Cylinders - Earlier drawings
on the Backhead Detail page show these lines in front of the backhead.
Yet these lines don't show on the photos. Furthermore, they would
block access to the hand holes. So in drafting this plan, they were
curled around the inside outer edge of the boiler. |
| Water Tube Hand Holes - These appear to be 40 circles with a bolt in the
middle on the drawing. While they are appear to be circles, it is likely
they were elliptical in shape. They are actuall drawin that way with a
vertical orientation. As the drawing
on the Backhead Detail page shows, the flanges were on the inside of the
outer boiler casing. If elliptical in shape, they could be removed through
the hole in the outer casing. The dots between the hand holes are the
backhead stay bolts. In one of the photos
on the Backhead Detail page, you can see the brackets and bolts that held
the hand hole covers in place. |
| Steam Pressure Gauge - is not shown on the drawing. Given his
seating position, it is likely the gauge was mounted to the front cab wall
in front of the fireman. |
| Tri-cocks - Are not shown in this drawing. Given their position
above the crew's head, the lack of space, the fact they were being phased
out and the unusual characteristics of this boiler, it is unlikely this
boiler had tri-cocks. |
| Entry doors - In all likelihood, these were not doors but openings.
They are drawn that way. To exit the engine, both the fireman and
engineer would need to lift their seats and exit through these
openings. Some NPC crews were concerned about the lack of collision
protection provided by the cab forward design compounded with the time it
took to exit. |
| Cylinders - This engine was built with parts from wrecked Baldwin
4-4-0s. Cylinder dimensions would have been consistent with Baldwin
4-4-0 design. However, they had been upgraded with Bill Thomas'
patented American Balance Valve. |
