To add to the answers about caboose whistle valves and as someone who rode
cabooses for a living during the first 10 years of my career, it should be
noted that use of the whistle, especially on long trains, was discouraged due
to the fact that a small brake pipe reduction from the rear end could cause
sticking brakes in the train.
Also, as noted by someone, many railroads
had different components on their cabs in addition to the whistle and brake
pipe valves. For example, the B&O had a rod and lever attachment
that allowed the conductor and/or flagman to close the angle cock from the
rear platform of the cab as well as a chain that was connected to the
operating lever and ended on the platform cross-rail. These were used to
cut helpers off on the fly, common on the B&O that used helpers
extensively east or Pittsburgh (all the way to Philadelphia). Other
railroads required the rear-end train crews to get down on the steps to lift
the cut lever, and lay down on the rear platform to close the angle
cock.
With regard to the brake pipe valves (both at the ends and
inside near the cupola or bay window), these were used extensively in
pre-radio days in order to stop a train if a defect was seen from the
rear-end. For example, sticking brakes, hot journal, shifted load,
etc. They were not used to put the air in the emergency position except
when the reason for stopping the train dictated an emergency
application. Many crews liked to use the valve on the rear platform
because it was not "stepped" like the ones inside the cab. This was
because the "stepped" valves were subjected to a greater effort in applying
the brakes, and could result in an accidental emergency application.
Brake applications from the rear end were done for a number of additional
reasons. For example, when entering the receiving tracks at Potomac
Yard, we would stop the train from the rear end as soon as we were in the
clear because the RF&P wanted the trains as near the north end of the
tracks as possible; also, our motel was right across a field from the north
end of the receiving tracks, so the flagman had a short walk over to where we
stayed. Usually moves like this were known by the engine crew, so they
would handle the train accordingly (i.e. slow down around the middle of the
receiving track, refrain from using the automatic brake, etc.).
Jim
Wolf
Belen, NM
