This section is from the book "The Cook's Decameron", by W. G. Waters. Also available from Amazon: The Cook's Decameron.
Ingredients: Cod or whiting, salt, onions, parsley, cloves, turnips, marjoram, chervil, milk.
Boil gently in a big cupful of salted water two onions, one turnip, a pinch of chopped parsley, chervil, and marjoram and four cloves. After half an hour pass this through a sieve (but first take out the cloves), and add an equal quantity of milk and a little cream, and in this cook the fish and serve with the sauce over it.
Ingredients: Cod, hake, whiting or red mullet, onions, parsley, mint, marjoram, turnips, mushrooms, chervil, cloves, salt, milk, cream, eggs-Put a saltspoonful of salt, two onions, a little parsley, marjoram, mint, chervil, a turnip, a mushroom, and the heads of two cloves into a stew-pan and simmer in a cupful of milk for half an hour, then let all the ingredients settle at the bottom, and pass the broth through a hair sieve, and add to it an equal quantity of milk or cream, and in it cook your fish on a slow fire. When the fish is quite cooked, pour off the sauce, but leave a little on the fish to keep it warm; reduce the rest in a bain-marie; stir all the time, so that the milk may not curdle. Thicken the sauce with the yolk of an egg, and when about to serve pour it over the fish.
 
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