The navy used to have these when I was a youngster in the early 80's.
it's a big coffee urn. Some of them have steam piped to them for 'brewing' and keeping the coffee warm. Each urn holds about 125 cups of coffee. Then they'd hold the temp at about 195 degrees for 18 hours... when it ran low they'd just throw more grounds on the top and hit the 'brew' button, water would squirt out into the grounds, into the pot it'd churn for a while, then the light would come on letting you know the next batch of paint remover was ready for consumption :icon_puke_r:
Seriously, some of the stewburners would tell the mess cooks. throw two cups of coffee in for first batch, when its time to redo, just throw another cup on top of the old already brewed mess that's also been setting there for 18 hours, and when the basket is full, only then throw it out and get a new one.
They came with huge coffee filters, although I do remember some kind of cloth filter thingie too they'd rinse out under hot water and reuse.....
Aaron
