because they looked like a standard Dreadnaught end without
the usual small side darts. American Car & Foundry increased
the rigidity of the dart-less end by adding dimples at the cor-
ners between each large rib [42]. Note that the four ribs in the
lower panel are larger than those in the upper panel and, in
accordance with A.R.A. recommended practice, are stamped
from heavier-gauge steel.
The original Dreadnaught concept of a series of large tapered
ribs continued to evolve as car builders developed their own
36. Improved
Dreadnaught 4/4 end
with main ribs shaped
like rolling-pins. Note
truncated top rib on this
car built in 1953.
36
37. Improved
Dreadnaught end on
car built by Pacific Car
& Foundry. Note non-
tapered top rib and six
small vertical indentations
in the hat section.
37
