Open 11 a.m. to 3 a.m. Monday through Thursday; 11 a.m. through 4 a.m. Friday and Saturday and noon through 1 a.m. Sundayd. MC, V. Prices: Pizza $2.25 to $13.00; same menu for lunch and dinner. Full meal with tax, tip and house wine averages $10.00.

In Chicago, Uno's is an institution, the originator of the pizza now known as "deep dish" or "Chicago-style." Since 1943, Uno's and Due's (its sister pizzeria with an identical menu) have made over 20 million pizzas.

In Washington, Armand opened the first "Chicago-style" pizzeria several years ago. According to myth, Armand is said to have rifled through Uno's garbage trying to discover the ingredients of their secret recipe. Whatever he found, he wasn't successful in imitating the pizza.

So, former Chicagoans rejoiced when Pizzeria Uno opened in Georgetown late last year. Finally, "Ike Sewell's original pizza" was here; he had already opened a pizzeria in Boston and we heard that it was as good as Chicago's. What joy! What promise! No more lugging frozen from Chicago!

The menu is limited (though it is hard to imagine that anyone would go there for anything but pizza) but includes soups, salads and sundries. The basic "deep dish" varieties are cheese, pepperoni, sausage and the "veggie." There is a combination "Numero Uno" which is filled with sausage, pepperoni, mushrooms, onions, green peppers and extra cheese, and the usual choice of single toppings. The pizza looks small, making you think that you should have ordered larger size, but that is deceptive since it is densely packed with ingredients.

A "deep dish" pizza should not be simply a thickened ordinary crust. The original has a dense, grainy consistency; it is crunchier and more brittle than "flat" pizza.

The Washington Uno's does achieve a tightly textured sponge-like crust similar to the original, but it is about half as thick and far less tasty.

The first layer on top of the crust is cheese (not tomato sauce as in most pizzas), and an acceptable mozzarella was applied generously. The Italian plum tomatos were undistinguished and on one occasion they tasted tinny, and the sausage was ordinary -- a crushing disappointment to anyone who has tasted the supreme original. The vegetables added to the pizza were fresh but they were not select. Seasoning varied widely from one visit to another: one time too bland, another too pepper, but once a fine blend of oregano and fennel.

The combination pizza, Numero Uno, is a good choice; the restaurant has succeded in proportioning the ingredients nicely rather than by the philosophy than "more is better."

Uno's does not live up to its promise, although advertising itself as "the original" promises an instant clientele. Had I idealized the original Chicago variety? To test that, I ate a Chicago import saved in our freezer for months. There was no contest: the Chicago pizza was far superior in every respect.

However, it is really not fair to judge the Washington Uno's against the Chicago original. The Washington establishment is at a strong disadvantage since it has neither access to ingreidents nor the experience of the original. But it is fair to judge it against local standards.

How does Uno's rate then? Unfortunately, only average.