Wash the mushrooms in water with a piece of flannel dipped in salt. Chop the anchovies and add them to the mushrooms with the mace, salt, pepper, ginger and onion. Put them into an enameled pan with vinegar to cover, and simmer until the mushrooms shrink.
When cold, put into airtight bottles, pour vinegar over them and seal.
Another Method: Wash the mushrooms in a little milk and water and wipe them with a piece of flannel. Cook for a few moments in some fresh hot milk and water. Take out and put into a jar with a little salt to season. Cover with a cloth. Allow to lie over night.
Scald some vinegar, pour it over the mushrooms, and seal in jars.