From 1861:
Vinegar is cheaply made. Here is the recipe:
To eight gallons of clear rain water, add three quarts of molasses; put into a good cask; shake well a few times, then add two or three spoonfuls of good yeast cakes.
If in summer, place the cask in the sun; if in the winter, near the chimney, where it may warm.
In ten or fifteen days add to this liquid a sheet of brown paper, torn in strips, dipped in molasses, and good vinegar will be produced.
The paper will, in this way, form what is called the “mother,” or life of vinegar.