Take half an ounce of Roman vitriol, half an ounce of saltpetre, six
pennyweights of salts of ammonia, half an ounce of verdigris, and
pound them upon a stone, do not use iron. Pound the salts of ammonia
first very carefully, then all the others together. Then mix them in
a glazed vessel[188] with as much water as shall make them have the
consistency of a sauce, stir them over the fire with a piece of wood,
& let them boil for such space as you can say two Paternosters. Do
not give them a strong fire for that would spoil them. Everything in
moderation. Let them cool, and use them as is here written in the
manner following.
FOOTNOTES:
[188] _Pentolino._