I just soak them for 10 min in water after I have enough to tone. They need to be good and wet though. I don't know if the dry, wet impacts archival issue though -- anyhow, it tones them nicely in a batch -- I flip 5 or six prints through at a time outside and take them out as they tone the degree I want. I do it outside because who wants that stuff inside, and you get the good daylight to judge (That is in an always overcast environment -- if you live in sunnyville, I dunno)

Dean