Wash the gold in water, and fuse in a crucible. So purified the gold is ennobled, and nothing is known to act upon it, save for the aqua regia . Yet without it I could not expect my thoughts to survive me. Ink must flow, but not drip or saturate the paper. It must be dark, and stay dark in spite of the air.
Many promising mixtures begin dark, but within a year or two, fade . . .
I tried various infusions and decoctions of leaves and barks in my search for an ideal ink. Some of these my brothers in the dye-works have use to color our robes their humble brown. I found it difficult to obtain the deep colors that an ink would require, however. One day by luck, I found an oak tree, infested by some disease that deformed its leaves into hard dry balls which are called galls, or nutgalls . I took a bag of these to find what they were caused by, and upon grinding and boiling them in a large iron pot, I found that the dark color was much increased.