Scale the fish, cut off the heads and tails, and divide them into four pieces.
Chop four or five small onions, and sprinkle a layer on the bottom of a stone jar; on this place a layer of fish, packing closely. Spice with black and cayenne pepper, cloves, allspice, whole peppers, and a little more onion. Then add another layer of fish, and so on till the jar is full. Arrange the roe on top, spice highly, and fill the jar with the strongest vinegar procurable. Place thick folds of paper on the jar under the cover, and bake for twelve hours. The vinegar will dissolve the bones, and the fish can be sliced for a tea-table relish.