Apple Butter (Without Cider)

To ten gallons of water add six gallons of the best molasses, mixing them well together. Put it into a large kettle (MUST NOT be boiled in a brass or bell-metal kettle) over a good fire; let it come to a hard boil, and skim it as long as any scum continues to rise. Then take out half the liquid, and put it into a tub. Have ready eight bushels of fine sound apples, pared, cored and quartered. Throw them gradually into the liquid that is still boiling on the fire. Let it continue to boil hard, and as it thickens, add by degrees the other half of the molasses and water, (that which has been put into the tub.) Stir it frequently to prevent its scorching, and to make it of equal consistence throughout. Boil it ten or twelve hours, continuing to stir it. At night take it out of the kettle, and set it in tubs to cool; covering it carefully. Wash out the kettle and wipe it very dry. Next morning boil the apple butter six or eight hours longer; it should boil eighteen hours altogether. Half an hour before you take it finally out, stir in a pound of mixed spice; cloves, allspice, cinnamon, and nutmeg, all finely powdered. When entirely done, put up the apple butter in stone or earthen jars. It will keep a year or more.