2.14. LOCAL FREIGHT BUILDUP
Handling local cars and building up local trains is almost
identical to the method used by a post office in gathering, sorting,
and delivering mail. Assume that a city street is 89 blocks long.
Bundles of mail come to the sorting table and a clerk sorts the mail
into the various pigeonholes in a mail rack. One pigeonhole may be
devoted to this particular street and for several hours all mail
addressed to this street is put in the appropriate pigeonhole without
regard to house numbers. Before the carriers are scheduled to leave,
the mail in the box is sorted again, and now, according to house or
block numbers. If 6 letter carriers cover 15 blocks each, the mail
would be sorted into 6 pigeonholes, each representing 15 blocks.
Each carrier would then receive the mail for his particular route.
However, if one carrier covered the entire 89 blocks, as many as 9
divisions might be made in the resorting. Each would represent
groups for roughly 10 blocks each, namely, 1001000 block, 11002000
block, 21003000 block, and so on. When the mail sorter consolidated
the 9 stacks, he'd have to be careful that the 8900block mail was on
the bottom of the pile, and that the 100 block was on the top.
Moreover, the successive order of all mail in between would have to
be correct. As the carrier walked along his route, the mail would
come off the top of the pile and match the house numbers of the area.
This system is almost identical to that used in switching and
delivering local freight. The cars must likewise be in successive
order when the train arrives at each station. It would be just as
impractical for a conductor to switch his train at each new station
as it would for a postman to reshuffle his stack of mail every time
he entered a new block.
a. Description of a local train. Most rail yards make up one or
more daily local trains. These trains, generally called for the same
time each dayand frequently occupying a place in the timetable
handle carload freight for the smaller stations along the line, which
are generally not served by the through trains. The crews on these
locals do switching work at each station, and sometimes they switch
freighthouse tracks and public and private team tracks and sidings
en route. Frequently, the locals carry a way caralso called a
peddler or a pool carwhich is one containing individual less
carload shipments for consignees at the various stations along the
way. The names for this car derive from the fact that it is unloaded
along the way, and that the crew, in unloading the individual
shipments, is reminiscent of a peddler unloading and delivering his
wares. The following subparagraph presents