Beef juice for invalids

Chop two pounds of lean beef small. Put a layer of this meat in the bottom of a glass jar and sprinkle over it a little salt. Then add another layer and a little more salt, and so on until the meat has been used. Set in a kettle. The water in the kettle should be cold and be heated gradually to the boiling point, after which it should be left to simmer for three or four hours, or until the meat looks like bits of white rags with the juice completely drawn out. Let all get cold together, then skim, and strain out the meat, pressing it hard.