DID YOU KNOW that the federal government recycles its cancelled checks into toilet tissue? This is one of the smaller gems in O Congress, by Donald Riegle, a congressman from Flint, Michigan. The diary of Riegle's activities between April 1971 and March 1972, it makes many of the standard journalistic (and by now boring) criticisms of Congress. It stabs fiercely at the seniority system by which power accrues to elderly, often senile, men. In Riegle's view, Congress is "a body of followers, not leaders" who pass the buck until public opinion and the press of history stops it.

Much of what Riegle describes about the failure of Congressional representation has been said before. Countless magazine articles, seminar papers, Ph.D. dissertations, and at least one popular study--The Cast Against Congress by Drew Pearson and Jack Anderson--have documented the malfunctions and weaknesses on Capitol Hill. But Riegle gives us substantially more than a deja vu montage of liberal opinion. He enables us to experience the tensions and frustrating re-orientation that ultimately demoted him from one of Newsweek's "five young men to watch in the Seventies" and a Nixon favorite.

The magic of O Congress springs from both the talents of Riegle and his assistant Armbrister and the nature of a diary form at itself. Days and weeks of political activity stand in stark contrast beside touching personal anecdotes. With artful honesty, Riegle discusses the stresses that destroyed his marriage. We also see his subsequent psychological recovery and relationship with another woman. These, combined with the simple, idyllic, and infrequent moments Riegle enjoys with his children, give O Congress an appreciable human impact. The result is rare; a political document of visceral as well as intellectual substance.

Riegle's political about-face, (some might say the end of his political naivete) can best be illustrated by the widening of the ideological chasm between himself and his original sponsor: Richard Nixon. The two men met in Cambridge in 1965, when Riegle, an "upward-bound, goal-directed hot-shot," was at the Harvard Business School. Nixon, in town to hire talent for his New York law firm, encouraged Riegle to run for a congressional seat in Flint, Michigan, then a Democratic stronghold.

Fighting hard, and with Nixon stumping for him, Riegle won the seat. But taking to heart the bromides of "conscientious representation" and "moral leadership", Riegle lobbied for change in a party too rigid and regressive to accomodate him. His disaffection dated from the 1968 Republican Convention's nomination of Spiro Agnew. The Michigan delegation tried to get John Lindsay, then George Romney, to make a floor fight. The rest is history; Romney received virtually no support and Lindsay wound up, to his everlasting regret, seconding Agnew's nomination.

THE HAYNESWORTH AND Carswell debacles, Vietnamization, and the purges of Charles Goodell and Walter Hickel only deepened Riegle's distaste for the Nixon Administration. As party policy becomes less his cup of tea, one wonders why Riegle continues to drink from it? Why doesn't he "do a John Lindsay?" The answer lies within the Riegle personality. Riegle possesses a singular optimism and fighting instinct. He is an idealist with a profound faith in the individual's capacity to shape his environment.

Then, too, there is the reassuring presence of like-minded House members, notably "Pete" McCloskey. McCloskey, more than anyone except Riegle, is a major reference point in O Congress. With unwarranted bravado, McCloskey took his crusade against President Nixon to New Hampshire, hoping to duplicate the now mythic McCarthy venture of 1968. But the McCloskey high horse, saddled with an apathetic electorate and an empty purse, pulled up lame at the polls, dumping not Nixon but McCloskey instead. The book ends with Riegle, McCloskey, and Harvard's own Chuck Daly administering it a broken hearted coup de grace.

O Congress makes excellent and sobering reading as a candid personal history of a somewhat impersonal institution. The book is a welcome landmark in the morass of literature on Congress. Making its points with control and dignity, it is inside dope that neither numbs nor oversensitizes.