Art from England's Moore -- and Churchill

For many, Henry Moore is England's major 20th-century artist. Indeed, none can match him in length of career to date (60 years) or worldwide reputation. A few others - Barbara Hepworth, Ben Nicholson, Francis Bacon, Graham Sutherland, Anthony Caro - might challenge him for this position, but none, in the final analysis, can match his overall accomplishments.

These are considerable, and they center mainly upon his work as a sculptor. Here, his range is extraordinary, from tiny bronzes and carvings to some of this century's most monumental public sculpture - and in style from representational to totally abstract. He is also a major draftsman (his World War II London air-raid shelter drawings are among the best works on paper produced anywhere since 1900) and a printmaker of note. As a matter of fact, were Moore's sculpture completely unknown, he would probably still be acclaimed a major artist on the basis of his drawings and prints.

The best exhibition of Moore's art I've ever seen is on view at the Metropolitan Museum here. ''Henry Moore: 60 Years of His Art'' consists of 200 works illustrating almost every aspect of his career. It begins with 50 carvings from the 1920s and '30s, moves on to a series of small stringed sculptures from 1937 to 1940, and then expands to include major examples of his mature sculptures, drawings, and prints - including a smallish bronze executed just last year.

It's an excellent exhibition, made all the more enjoyable and impressive by the space within which it is displayed. The Robert Lehman Wing has never been better used. Its various open and enclosed areas are perfect for the display of large and small sculpture, and the depth of its rotunda gallery (as seen from above) makes it ideal for viewing sculpture from varying heights and angles.

At the Metropolitan Museum through Sept. 25. TA Japanese national treasure

If Japan doesn't confer ''National Treasure'' status on Isamu Noguchi, the United States should. Americans, as a matter of fact, have the better claim on him, despite his Japanese father and early schooling in Japan. He was, after all , born in Los Angeles; his career was established and sustained in New York, and his mother was part American Indian.

All this, of course, had little to do with his art - except as it contributed to his deeper understanding of both Eastern and Western art and helped him bridge the best of Japanese and American culture.

That is precisely what he has done, and in ways that speak with equal significance to both countries. In fact, one could just as well say that Noguchi's sculpture transcends allm cultural differences through the universal language of form.

That, at any rate, was my impression as I entered the Pace Gallery here to view his current exhibition. I was quite overwhelmed, both by the quality of the individual pieces and by the manner in which they related to one another. I felt , as I've always felt when in the presence of Noguchi's art, that he is an artist of extraordinary sensibility and that very few artists in this century have come as close to perfection as he.

The sculptures on view are recent (many were executed last year) and extremely simple. Most are of basalt or granite, although a few are joined to sections of steel. The effect is one of large, handsome stones and rocks slightly modified by the hand of man, and occasionally attached to, or pierced by, stark steel shapes. While this may sound overly simple and unimportant, the end result, thanks to Noguchi's talent and sensibilities, is an exhibition of uncommon beauty.

At the Pace Gallery, 32 East 57th Street, through June 17. Churchill's best

It is common knowledge that Winston Churchill loved to paint and that he was good at it. He may, in fact, have been the most famous good amateur painter the Western world has ever known. Photographs of him hard at work before his easel appeared regularly in the newspapers during the late 1940s and the 1950s. And he took advantage of every opportunity to praise painting as the best of all pastimes.

He had every reason to know, having spent a great deal of his leisure time in front of a canvas. Painting entered his life shortly after his dismissal from the Admiralty in 1915. Distraught, frustrated, and with unwanted time on his hands, Churchill began to dabble in oils. Although his first attempts weren't particularly successful, he was fascinated by what paint could do. He continued to wield his brush - except during the war years - until 1957.

Although Americans have heard a great deal about Churchill's paintings, they haven't had the opportunity to see more than a handful. This is no longer so, thanks to a large exhibition of his oils now on view at the National Academy of Design here. ''Winston S. Churchill: Painting as a Pastime'' consists of 51 of his paintings on loan from various private collections and spans his entire career as an amateur painter.

Good as many of them are, it's obvious he was not a professional, and that he didn't have to compete as a professional. Had he done so, his work, I'm certain, would be unknown to us today.

But that's really beside the point. What matters is that he really tried to create art and not a series of tinted photographs. And that they were done by Winston Churchill.

It's an extremely pleasant and quite accomplished show. His modified Impressionist style was perfectly suited to his personality and allowed him to express himself with warmth and verve. In all, it's an impressive performance.

After its closing at the National Academy, 1083 Fifth Avenue, on July 3, this exhibition will travel to the Smithsonian Institution in Washington, D.C., opening there in mid-September.

From the Royal Academy

Also at the National Academy is an excellent selection of paintings and drawings from London's Royal Academy. These mark the first time in its 214-year history that the academy has sent a major exhibition of its holdings to the US. The 41 works on display date from the 18th and 19th centuries and include examples by, among others, Constable, Turner, Gainsborough, West, Lawrence, and Sargent.

Particularly outstanding are Constable's ''The Leaping Horse'' and Sargent's ''An Interior in Venice.'' And I was pleased to encounter Raeburn's famous and charming ''Boy and Rabbit.''

The exhibition leaves the National Academy after June 15 and will then travel to the Seattle Art Museum (June 19-Aug. 14); the New Orleans Museum of Art (Sept. 10-Oct. 23); the San Antonio Museum of Art (Nov. 6-Dec. 25); the Virginia Museum, Richmond (Jan. 15-Feb. 26); and the Delaware Art Museum, Wilmington (March 10-April 15, 1984).