This section is from the book "The Complete Cook", by J. M. Sanderson. Also available from Amazon: The Complete Cook.
Having cleaned, wipe them thoroughly dry, and keep them in a coarse cloth an hour or two before using. In case any moisture should remain, flour them all over, and again wipe it off. They may be fried either with or without bread crumbs or oatmeal. If bread crumbs are to be used, beat up an egg very finely; wash over the fish with a paste-brush; then sprinkle over it bread crumbs or oatmeal, so that every part may be covered, and one part not be thicker than another. Lift up the fish by a fork stuck in the head, and shake off any loose crumbs that may adhere. Have plenty of fat in your pan, over a brisk fire, and let it quite boil before you put the fish in. The fat may be salad oil, butter, lard or dripping. If sweet and clean, the least expensive answers as well as the best, but let there be enough to cover the fish. Give the fish a gentle shove with a slice, that it may not stick to the pan. In about four or five minutes one side will be brown; turn it carefully, and do the other; which, being already warm, will not take so long. The best way to turn a large sole, is to stick a fork in the head, and raise the tail with a slice, otherwise it is liable to be broken with its own weight. If the soles are very large, it is a good way to cut them across in four or five pieces, by which means the thick parts can have more time allowed them, without overdoing the thin. The very same rules will apply to the frying of Dutch plaice, flounders, eels, jack perch, roach, and other fresh-water fish. Jack and eels to be cut in pieces three or four inches long. Sauce, anchovy, parsley and butter, or melted butter flavoured with mushroom catsup. Garnish, sprigs of parsley or lemon juice.
 
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