TO PRESERVE BUTTER No. 2.
Reduce separately to a fine powder, in a dry mortar, 2 pounds of the best common salt, 1 pound of saltpetre and 1 pound of loaf sugar; sift one of them over the other on a sheet of paper, then mix them well together and they are ready for use. 1 ounce of the preparation is enough, to a pound of butter, and if well worked in will preserve it sweet for three years. This is worth giving a trial.