Engine Room (Forward)
The "fire room," which comprised the forward end of the engine
room, lay immediately aft of the boilers. Here crew tended the
Monitor's boilers and controlled the main engine. Both
required considerable maintenance. Crew members continually
fed the boiler fires and tended the coals, while engineers and
sailors monitored the various pressure and temperature gauges
on an hourly basis.
As on the
berth deck, all lighting in the engineering areas was artificial, and
the iron walls bore white paint to reflect what little light
there was. In good weather, one could open the crew's hatch in
the overhead, but the area mostly remained sealed so the
blowers could efficiently fan the furnace fires.
Aft of the boilers was the Monitor's main engine.
Another original conception of the ship's inventor John
Ericsson, the engine was not unique in design but it was
unique for then-modern naval warships. The vibrating
side-lever engine had one main cylinder that housed two
pistons operating on a horizontal plane instead of the more
traditional vertical plane. On each side of the engine lay a
"rock shaft," which a short arm connected to the piston trunk.
At the aft end of the rock shafts, arms attached to the
propeller shaft via connecting rods. As the pistons slid back
and forth, the rocking motion translated into rotation at the
propeller shaft.
The vibrating side-lever engine allowed rotation of the
propeller shaft to be applied at a 90-degree angle to the main
cylinder, while the horizontal design of the cylinders enabled
Ericsson to place all of the machinery low in the hull below
waterline and behind the Monitor's protective armor.
At the back of the engine was the valve chest. This area was
"operation central" for the main machinery. Using a series of
levers, cranks, and wheels, the men worked the vibrating
side-lever engine at the captain's whim.
Below the valve chest lay two of the Monitor's bilge
pumps. These pumps were rated at 2,500 gallons per minute,
more than capable of keeping the bilges dry. Ericsson also
equipped the ship with a centrifugal bilge pump that was rated
at over 3,500 gallons per minute. The blower drive pumps were
mounted floor-to-ceiling at the outboard sides of the fire
room. The small steam engines drove the large blowers with
thick leather belts.
The engine itself stood on a raised platform, which crew
members accessed via a set of stairs on the starboard side.
From this area, sailors had access to all of the main engine's
moving parts. Vigilance was essential during operation of the
main engine. The engineering crew had to ensure all moving
parts were sufficiently lubricated for peak performance. A
damaged piece of machinery could take weeks to replace, as
most of the parts would have to be fabricated.