Green Walnuts

When the juice is in the almond state, break them in two, detach the white parts with a circular movement, then throw them into cold water in which a little powdered alum has been dissolved; drain through a colander, and throw over a handful of white salt, two finely cut up shallots, and put them into a salad bowl, adding the juice of two lemons; roll them in their seasoning, and serve on side dishes.