The following recipe was copied from Hutchins' Improved Almanac (N.Y.), 1837, p. 27, and submitted by Susan Swartzburg. It helps explain why the ink in old documents sometimes disappeared after a while, taking the paper with it.
"Excellent Ink, and easily made. Into a ten gallon keg, put three pounds of copperas, well pulverized. Take three pounds of logwood, and boil it in six or seven gallons of rain or pure river water, and when it has boiled half an hour add four pounds of nut galls, broken up, and a quarter of a pound of alum. After another half hour's boiling, pour the whole of the materials into the keg, stir the contents well together, and let it remain a week, stirring the whole several times a day. Then put into the keg half a pound of gum arabic, in powder, and one pound and a half of sugar candy. Leave the mixture a week longer, stirring frequently. After three weeks' rest and setting, the ink may be used with pleasure, growing better with age. To keep it from moulding, add a dram of cloves and cinnamon, in powder, with an ounce of anise seed. To render the ink of a beautiful blue black, add to the above contents a quart of sulfate of indigo, reducing it to small pieces, sprinkling a little water on it, and the next day add to it two pounds of sulphuric acid, and leave it to digest in a warm place. [from] Silliman's Journal."