Chestnut Soup

Scald, peel, and scrape fifty large chestnuts; put these, into a stewpan with two ounces of butter, an onion, four lumps of sugar, and a little pepper and salt; and simmer the whole over a slow fire for three-quarters of an hour; then bruise the chestnuts in a mortar; remove the pulp into a stewpan; add a quart of good brown gravy, and having rubbed the puree through a tammy, pour it into a stewpan; make it hot, and serve with fried crusts.