All fish but salmon (which is put into warm water to preserve its color) should be placed in salted cold water, with a little vinegar or lemon-juice in it, to boil. It should then boil very, very gently, or the outside will break before the inside is done. It requires a little experience to know exactly how long to boil a fish. It must never be underdone; yet it must be taken from the water as soon as it is thoroughly done, or it will become insipid, watery, and colorless. It will require about eight minutes to the pound for large, thick fish, and about five minutes to the pound for thin fish, after the water begins to simmer, using only enough water to cover it. When done, drain it well before the fire. The fresh-water, or any kind of fish which have no decided flavor, are much better boiled au court bouillon, or with onions and carrots (sliced), parsley, two or three cloves, pepper, salt, vinegar, or wine - any or all of these added to the water. The sea-fish, or such as have a flavor prononce, can be boiled in simple salted and acidulated water.
If you have no fish-kettle, and wish to boil a fish, arrange it in a circle on a plate, with an old napkin around it: when it is done, it can be carefully lifted from the kettle by the cloth, so that it will not be broken. When cuts of fish are boiled, you allow the water to just come to a boil; then remove the kettle to the back of the range, so that it will only simmer.