A rail shipment may also be held until enough cars
are destined for a
certain area. Next to shipping by boat, shipping by train is probably the
slowest method to get something some where, as far as total transit time. A
truck can be anywhere in the US in a matter of 4 days. For perishible
items, trucks are far more viable. Also, trucks generally ride better than
rail cars, so delicate cargoes benefit from the air-ride suspension systems.
I've been told UPS has started holding the ground trucks
until they fill up, where they used to have a timer; timer
fires, truck rolls, full or not. When fuel costs jumped a
couple of years ago they changed this. May not be true...
-dq