Take the stomach from the calf as soon as it is killed. Do not wash it, but hang it in a dry, cool place for four or five days. Then turn it inside out, slip off all the curd nicely with the hand, fill it with a little saltpetre mixed with the necessary quantity of salt, and lay it in a small stone pot. Pour over it a small teaspoonful of vinegar, and sprinkle a handful of salt over it, covering it closely to keep it for use. Never wash it; that would weaken the gastric juice, and injure the rennet. After it has been salted six or eight weeks, cut off a piece four or five inches long, put it in a large mustard bottle, or any vessel that will hold about a pint and a half. Put on it five gills of cold water, and two gills of rose brandy. Stop it very close, and shake it always before using. A tablespoonful of this is sufficient for a quart of milk. It must be prepared in very cool weather, and if well done will keep more than a year.