some stone litho info

I'm a monitor at a print shop and specialize in stone and plate lithography so sometimes I'll talk about techniques and such that I want to remember.
Today I learned the proper way to take a break in the middle of printing off a stone. Once you've pulled your BAT, give it two passes of ink and then gum down the stone with a sponge. Then you can take your coffee break and when you come back, just wash off the gum really well with water and then continue printing.
Later on, I'll talk about printing in colour off the stone for multicolour prints (in my case 4). I'm a bit fuzzy on the details since I generally work in B&W.