Brunch is so useful a form of entertaining that it almost restores one's faith in the fruits of compromise. Of late, however, the equilibrium of this artful institution appears to be threatened. It is, quite simply, a case of too much breakfast and nout enough lunch!

Fruit juice, eggs presented in some oddly inappropriate organic container - a tomato or several mushrooms - and a collection of outsized pastries do not constitute a proper brunch, even if a drink or two is thrown into the package. What is lacking is something substantial and satisfying. After all, the word brunch owes two-thirds of its pedigree to "lunch."

It would be foolish to raise this objection during summer when the outdoor brunch season is in full swing. High humidity and rising temperatures, always foes to reason, can be depended on to wither appetites. Furthermore those who enjoy food too well throughout the rest of the year usually make a tardy effort to become trim for the beach.

Now, however, with dank, dark days making us chilly and visions of howling winds, cold and snow likely to be realized at any time, eating becomes a form of solace as well as something sensible. Brunchgivers, at the very least, should turn for inspiration to the English breakfast, or our own of bygone times. Chops have a place in such a meal. So do potted meats, pates and dishes created from leftover and poultry.

A number of dishes that would brighten any brunch for those with a midday appetite are offered here.

But, pallid as the contemporary formula breakfast is, don't rule out the standbys. Eggs, bacon and sausage are perfectly acceptable. Fruit juice is fine, but a compote of cooked fruit might be better. Don't stop there. Offer homemade biscuits, offer cheeses, serve an array of smoked fish and a dessert or two. Make sure the coffee is strong and assertive.

As for the other beverages, the Bloody Mary's place of honor at brunch should be secure. At this time of year, however, hot wine punch can make a hit and champagne is welcome any time. Brunch also is a good time to test people's reactions to rose. They may not be wide awake enough to protest when it appears and then discover that they like it. Several American variations on the pink wine theme - Ste. Michelle, Taylor and a number of California wineries - are relatively dry and taste like wine instead of soda pop. California's "mellow" - meaning not dead dry - Chenin Blancs (Concannon has a real winner, as does Souverain) are white wines that are pleasant alone or with food. German whites, low in alcohol and slightly sweet, are appropriate, too. WELSH RABBIT (4 to 6 servings) 1 tablespoon butter 1 pound sharp cheddar cheese, grated 1 cup beer or ale 1 teaspoon powdered mustard Salt and black pepper to taste 1/2 teaspoon cayenne pepper 1 or 2 toasted English muffin halves per person

Bring water to a boil in the bottom half of a double boiler. In the top, allow the butter to melt, then add the cheese. Stir until cheese shows signs of melting, then mix in beer and seasonings. Continue to stir until well mixed and hot. (For a slightly thicker texture, add a beaten egg to the hot mixture and stir well.) Serve over muffin halves. ELSIE WOLFE'S DEVILED MUSHROOMS (8 servings)

Wash and clean fresh mushrooms (about 1 1/2 pounds). Fry whole in butter to which has been added a little lemon juice and 1/2 cup of water, salt and pepper. When cold, slice thinly and fry again in butter and sprinkle well with chopped shallots and parsley, and add 1/2 cup of thick fresh cream. Prepare slices of toast, butter the toast and spoon slices of fried mushrooms carefully on the toast, so that they overlap one another. Pour over them a hollandaise sauce which has been highly seasoned with dry English mustard, paprika and plenty of cayenne pepper. Brown in the oven and serve very hot.

Hollandaise sauce: Put the yolks of 3 eggs in a small saucepan, a little salt and pepper, 3 tablespoons of water and 1 ounce of butter. Cook in a double boiler. When it begins to thicken, lower the flame, and add 1/2 pound of butter, little by little, and whip strongly with a beater - raising the flame occasionally while whipping. ELIZABETH DAVID'S FRENCH FONDUE (4 to 6 servings)

Put 1/2 cup of dry white wine into a saucepan with a chopped clove of garlic and cook until wine is reduced by half. Strain it and leave to cool.

In a bowl, beat 6 eggs with 1/2 pound of grated gruyere cheese, 2 ounces of butter, some ground black pepper and a little salt. Stir in the reduced wine and pour the mixture into an earthenware or other fireproof dish and stir over a low fire until the mixture forms a creamy mass, well amalgamated, but in no way resembling scrambled eggs.

Serve at once in the pan in which it has cooked, and boiling hot. Each person should have a supply of squares of bread or toast. Dip in with forks. NINA SUNDELL'S MUSHROOM RISOTTO (10 servings) 3/4 ounce dried shtraw mushrooms*(FOOTNOTE)

* Available in Oriental groceries and some supermarkets (END FOOT) 3/4 ounce dried European mushrooms 3/4 pound fresh mushrooms, sliced 4 tablespoons chopped shallots, or 2 small onions and 2 cloves garlic, minced 6 tablespoons butter or margarine Salt, freshly ground pepper and nutmeg 6 tablespoons olive oil 2 cups medium grain domestic or imported Italian rice (do not use long grain) 2 quarts homemade chicken stock or 1 quart canned chicken broth plus 1 quart water 1/4 cup dry vermouth or dry white wine 1/2 cup freshly grated parmesan cheese

Soak dried mushrooms in 2 cups water for at least 30 minutes. Strain liquid through cheesecloth and wash off mushrooms. Saute fresh mushrooms in 2 tablespoons butter with 1 tablespoon shallots. Season with salt, pepper and a small amount of nutmeg.

Heat 3 tablespoons of butter and the oil in a large pan or casserole with a heavy bottom. Add remaining shallots and cook over medium heat until golden. Add rice and stir until grains are well coated with oil and turn transparent. Add 1/2 cup or broth, let it come to a boil and bubble for 30 seconds. Turn heat as low as possible, stir and let cook uncovered for 10 minutes. Add the mushrooms and their liquid. Now stir often, every 3 minutes or so, adding liquid as the rice begins to dry up First add the vermouth, then the remaining stock, 1 cup at a time.

At the end, the mixture should be slightly soupy. Stir in the remaining 2 tablespoons butter and 1/2 cup parmesan. Serve in soup bowls and have more cheese and a pepper mill on the table. JAMES BEARD'S CODFISH LYONNAISE (6 to 8 servings) 1 pound salt cod 6 medium potatoes, sliced 2 medium onions, sliced Butter or oil Chopped parsley

Soak cod in cold water for several hours. Saute potatoes and onions slowly in butter until soft and golden. Flake the codfish and brown it nicely in butter or oil; combine with the potato-onion mixture and let it cook down for a few minutes. Sprinkle generously with chopped parsley. GRILLED OYSTERS BALTIMORE (2 servings) 1 dozen large oysters Peper 1/4 cup clarified butter 1/2 cup fresh bread crumbs 2 slices toast 2 slices ham (Smithfield style preferred) Lemon and parsley for garnish 1/2 cup light cream sauce 2 tablespoons diced celery

Dry oysters on a towel, sprinkle with pepper, dip in butter and crumbs. Broil quickly to light golden color. At the same time broil the ham slices. Cover toast with ham, place 6 oysters on each piece of ham; garnish top with slice of lemon and sprig of parsley and pour around it the light cream sauce with chopped celery cooked into it. ROAST BEEF HASH (4 servings) 4 tablespoons butter, or half butter and half oil or beef drippings 1 small onion, diced 2 cups chopped leftover baked or boiled potatoes 1/3 cup cream 1 pound cooked lean roast beef, diced Salt and freshly ground pepper

Saute onion in 2 tablespoons butter until soft but not brown. Scrape into a bowl and mix with potatoes, cream, beef and seasoning. Rub remaining butter over the inside surface of a cast iron frying pan or shallow baking dish. Place the hash in the pan and spread flat. Bake in a preheated 350-degree oven for 30 minutes, or until top is brown and crisp.