One answer to a shortage of wall space in art galleries is, of course, to plaster pictures like stamps in an album, fairly solid from the wainscot to the ceiling.

If art is art, after all, the mind can perceive it perfectly well when it is jammed in with scarcely 2 inches between paintings; and if you really think of it, there is no reason to treat pictures as if they were mere decorative objects requiring a whole wall for each.

The sensible 19th-century style of display is illustrated at the large (200-odd pictures, sculptures and models) exhibit at the National Collection of Fine Arts that opened yesterday at 8th and G Streets NW.

Joshua Taylor, the director, was sticking on labels here and there as the show opened, while down in the courtyard (one of the most attractive in the capital with its fat iron fountain basins and earnest little squirtpipes doing their best to keep them a quarter filled with water) people strolled sipping punch and adjusting straw hats and open collars.

The Collection has been 10 years now in the historic old building - the old Patent Office, which was a hospital and morgue during the Civil War, and the site of Lincoln's inaugural ball. Congress considered a bill to tear it down in 1957 and use the space as a parking garage but in one of its more inspired afternoons decided not to.

As early as the 1820s a citizen, John Varden, started collecting things he thought worthy of the capital, and over the decades all sorts of things have been accumulated, some of them undoubtedly art.

As one enters, he sees to the left an odd "Massacre of the Innocents," in which an artfully draped man is fixing to dash a quite large baby on the rocks. An opposite wall is filled with paintings of Indians - formal portraits by John Mix Stanley and George Catlin.

Handsome bronze open-work gate panels by Paul Manship (the Collection has very large Manship and Zorach collections) and a wonderful little cast-iron balustrade from Louis Sullivan's remarkable Carson, Pirie-Scott Building in Chicago.

There are jewels and miniatures, an Audubon painting of satisfied-looking birds, and a room full of posters illustrating some of the vast number of special shows held over the years. The Collection and the Renwick, its sister gallery, mount 28 shows a year.

Very little of the art now on display through Sept. 4 is ever seen by the public because of the shortage of display space.

Everything in the gallery, however, is catalogued and readily available for study, whether in storage or not.

Under the trees, silver bowls sat on white-clothed tables holding punch of an anusual salmon-rose color, largely lemonade and ginger ale but blushing deeply, and basins of dead-ripe strawberries and orange slices.

So perverse is mankind, however, that many passed up the free punch and bought food and drink in the little Patent Pending restaurant opening on the courtyard. A considerable group of piegons gathered for crumbs and were disappointed. Punch and strawberries make few crumbs. Popcorn, if one may say so, would have been nice.