IF YOU ARE LOOKING for the name of the girl described by Jackie Kennedy as the one "my husband is said to be sleeping with" or the identity of the female correspondent who left her unmentionables under the piano at a White House party, Robert Pierpoint's lips are sealed. He is a gentleman, and gentlemen don't tell!

The the same time, Pierpoint is a journalist, and there is nothing which fascinates journalists more than chatting about their trade. This he does in a manner both entertaining and instructive to those who need to be told that the Executive Mansion is staffed by human beings subjet to all the foibles of mortal man. To sum it up, At the White House is a book which is candid, amusing, but not mean.

The Pierpoint reticence does not extend to the six presidents whom he covered for CBS. He is blunt about what he describes as the Kennedy "extramarital activities" which included dalliance "with a lively and sexy college dropout" while resting at Palm Beach after the 1960 campaign. He describes Lyndon B. Johnson as "crude" and "overbearing" and relates a tasteless remark made by LBJ to his wife -- a remark which Lady Bird handled with her accustomed poise and grace. Richard M. Nixon was a man who "disliked people" but could fool "many observers into believing just the opposite." Carter he regards as a man who "did not how to use the power he had acquired" and who suffered from a "streak of hostility" that came through to the public during the 1980 campaign. Only Dwight D. Eisenhower and Gerald Ford emerge as fully likable human beings.

One of the interesting aspects of this book is that Pierpoint is a man who can find virtues even in presidents he does not like. For example, he speaks of Johnson as "most qualifed" and a man who "genuinely cared about the poor and underprivileged." He predicts that LBJ will be regarded as one of America's "outstanding presidents" despite his "failure in foreign affairs." In that field, he belives that Nixon did "the best job." His other ratings are somewhat more nebulous although he speaks nostalgically of the Kennedy charm and appears to believe the JFK had tremendous potential for service, unfortunately cut off by an assassin's bullet.

For most readers, the impact of this work will lie primarily in the sweeping picture presented of White House life in a style somewhere between gossipy and anecdotal. At times the picture is too kaleidoscopic -- a result either of Pierpoint's training as a television journalist or of too many memories crowded into too few pages. Georgia quail hunts with Carter merge into the Cuban missile crisis with Kennedy which, in turn, fades into Eisenhower's bewilderment over a cigar-smoking woman journalist and then into a Pierpoint exclusive on an LBJ appointment which the Texan was trying to keep secret. It is something like a mill which grinds grains both large and small and drops the final product into a single bin.

There is a Thurberesque quality to some of the stories. Jackie Kennedy's remark (in French, incidentally, to a French correspondent) identifying her husband's alleged inamorata appears to this reader as a vignette from The War Between the Sexes. And the question of just how an item of reportorial underwear under a grand piano in the huge entry hall of the White House (during a party given by the Johnsons for Indira Gandhi) will tantalize me for years.

On the whole, Pierpoint is kindlier to first ladies than he is to presidents. He was somewhat bothered by being cut by Jackie Kennedy for not apparent reason but he is quick to describe her on other accasions as "a gracious and regal hostess" who was "warm and considerate" to guests. Mamie Eisenhower he describes as a "warm, kindly person" who suffered her husband's excesses "with grace and dignity." He was surprised to encounter a Pat Nixon -- whom he had known as an "independent and gregarious teacher" at the high school he had attended in California -- who had become "almost terrified" of the press. However, she finally loosened up on a trip to Peru where she displayed genuine concern about the suffering of the people. Betty Ford was "refreshing" in her determination "to be her own person" and Rosalynn Carter was "a tremendous political asset for her husband."

In the final analysis, the most impressive feature of this book is that Bob Pierpoint survived to write it. Any person who can retain something of a sense of humor after 23 years in the Byzantine atmosphere of the White House staff and the White House press corps is a viable candidate for sainthood. I hope someday to see a sequel in which he describes how he did it.