Re: Tank cars

Len wrote:
[...]
> I never got a good explanation why, but several materials were
> actually loaded through the 'discharge' valve on the bottom of the
> car. The air in the car vented out through a pipe on the top as it
> filled. It was your job if you overfilled and blew material out the
> top.
> 
> Len
> 

I suspect it was to reduce venting of gases. In you fill through the top 
valve, then gases from the fluid will mix with the air being displaced 
and vented outside the tank.

-- 
wolf k.