I think you mean the dust-on process (" Einstaubverfahren" in german) where
a chromat/gelatine ( with gum, sugar and/or glycerin)
is exposed under a positive.The unexposed gelatine-layer is soluble in
water and sticky but after exposing it loses this characteres and when such
print is dusted with pigment-powder the unexposed parts hold more pigment
than the exposed.
But what I know and J.M.Eder said in "Handbook of Photography" -1926) the
dust-on process not really needs a powder box, because the dusting can be
done on a plaine surface with a brush( the fingers and your breath).
Good luck
Harry
Harald Leban
Austria/Europe
hlebanphot@compuserve.com
http:\\www.aperture-photo.com
platinum-room