Hi Al,

Both market and technology brought about the 50' box car.

In a nut shell "The big railroads wanted to haul more goods and reduce the
tonnage they had to haul. It took 125 40 foot boxcars to equal 100 50 foot
boxcars. The reduction would be 25 less 40 foot boxcars times their empty gross
wait." Source - 40 Foot Boxcars and Their Different Types by _Michael W.P.
Ball_ (http://www.ideamarketers.com/library/profile.cfm?writerid=20596)

Along with the return of hundreds of thousands of the military after WW II,
the consumer market grew demanding more and larger products, especially
furniture and automobile parts. So the RR's had to find a better way to transport
these goods.

Technology helped with the use of welding instead of rivets to build
stronger not only longer box cars, but box cars with a higher inside height and
wider doors. Technology also brought upon the use of fork lifts and pallets to
carry and stack higher loads.

These are just a few of the reasons.

Dick Kashdin
Clarence, NY