--- In STMFC@yahoogroups.com, Garth Groff <ggg9y@...> wrote:
through the roof vents, and maybe to a lesser extent through thesmall
side vents. I don't think any of the Linde boxcars wererefrigerated, at
least I've never heard of it. The cars I examined certainly didn'thave
diesel engines like refrigerators.Then maybe the vents are similar to pop valves that open when the
pressure inside reaches a certain level. I don't think shippers want a
permanently open vent on top of a box car since rain can blow in.