OF THIS PAIR of books devoted to the American past, with occasional forays into the present and future, by far the better is The National Museum of American History; it's heavy enough to break your lap, but it is crammed with first-rate photographs and the text is surprisingly good. By comparison with James A. Michener's U.S.A., it is also a real book, not a production or package.

Shirley Abbott, author of the text that accompanies 422 pictures of items on exhibit at the Smithsonian's National Museum of American History, correctly perceives that the dominant themes in the museum are American industriousness and inventiveness. She quotes de Tocqueville: "It would seem as if in the United States every man's power of invention was on the stretch to find new ways of increasing the wealth and satisfying the needs of the public. The best brains in every neighborhood are constantly employed in searching for new secrets to increase the general prosperity, and any that they find are at once at the service of the crowd."

What the museum presents is a display that is "rich in the touchable and the commonplace." It is an extraordinary collection of the ordinary: "Not many nations are willing to measure their identity by such ephemera as old toothbrushes and unused army boots, or to admit freely that their historic spirit resides in walking-beam steam engines, combine-reapers, calculators, permanent-wave machines and atom smashers. In no other capital city is there any such institution as this museum."

What we find between the covers of this book is what we find in the museum itself; the book is a catalogue, albeit an exceptionally expensive one, of the museum's most interesting and unusual exhibits. In no particular order they include:

George Washington's dentures, which were not made of wood. The interior of a Maryland sharecropper's house. A peddler's wagon. A one-hoss shay. Benjamin Franklin's printing press. Early machine-made clothing. The cotton gin. A Model T Ford. An Automat. Isaac Singer's sewing machine. Alexander Graham Bell's telephone. Thomas Alva Edison's hand-cranked recording machine. A Merganthaler Blower linotype machine. A timber-frame house. A balloon-frame house. The interior of Stohlman's Confectionary Shop in Georgetown. The interior of John F. Kennedy's campaign airplane, the Caroline.

On and on it goes. The cumulative effect of reading the book is the same as that of touring the museum: exhausting and exalting. More than any other museum or public building in the country, the National Museum of American History celebrates the variety and energy of the country; it is vivid proof that in many important respects, what we make is what we are. In this book, the museum is faithfully and handsomely represented. Shirley Abbott's literate text focuses with equal clarity on broad themes and narrow specifics, and the photographs (almost all of which are in color) are splendid.

By contrast, James Michener's U.S.A. is a spinoff and a ripoff. The spinoff is from a television series of the same title that will be syndicated next year; the ripoff is of James Michener's hundreds of thousands of devoted admirers, who are going to buy this book thinking that their hero wrote it and who are going to find that he did not.

A "Publisher's Note" at the beginning reads: "Essentially, the text of this book is from the script of the television series 'James Michener's U.S.A.' In addition, there are some contributions by the editor. Such contributions are indicated by a (box) at he beginning and the end of these portions of text." That is a considerable misstatement; the phrase should be "many contributions by the editor," not "some." From Michener we get: a one-and-a-half page foreword, a fatuous epilogue called "Looking at Today and Tomorrow," and transcripts from the TV show. The rest is the work of Peter Chaitin, the editor.

And Chaitin's work is considerably better than Michener's. As the book makes its inexorable progression from North to South, from East to West, Chaitin provides competent if uninspired background on each locale's history. Michener, by contrast, is good principally for a running exhibition of bromides: "The frontier is not limited to space. America's own inner space is ripe with challenge. Our future resides with our youth. . . . It seems to me that football has become a metaphor for the American spirit. . . . Change is a constant in American life." Everywhere he turns he is a booster, often a naive one; "Atlanta," he mistakenly intones, "is known as a model of racial cooperation."

James Michener's U.S.A. is bubble-headed from first page to last. By contrast, even Michener's leaden, interminable novels are works of art. This book aims to exploit his popularity and gives his readers nothing of value in return--unless you count 17 pictures of James A. Michener, which is the number to be found herewith. By turns he looks kindly, public-spirited, grandfatherly and wise; by lending his name to this enterprise, he also looks greedy.