MIDAIR. By Frank Conroy. Dutton/Seymour Lawrence. 149 pp. $15.95.

IT HAS BEEN nearly two decades since the publication of Frank Conroy's early autobiography, Stop-Time, a book that was lavishly praised when it first appeared and that, I am happy to report, reads every bit as well now as it did then. Stop-Time is many things, but above all it is an exercise in the awakening of memory, an effort at self-discovery through the gradual, random recollection and interpretation of the author's past. That process is now continued in Midair, Conroy's second book; though its eight chapters are described as short stories, they are more usefully considered as a continuation, or an extension in a somewhat different direction, of the autobiography.

To speculate about the degree to which the details of these stories are or are not autobiographical is both pointless and beside the point; suffice it to say that anyone who has read Stop-Time is going to recognize Conroy as the principal figure in most of them and is going to learn a good deal about what has happened to him since 1967. But by calling these pieces stories rather than memoirs, and by covering himself with at least a thin cloak of invention, Conroy focuses the reader's attention on his imagination rather than on himself. The object of that imagination once again is memory and the past. As he writes in a fine story called "Car Games":

"He remembers all this as he sits waiting for his wife to bring coffee into the living room. At the age of thirty-five he finds himself daydreaming constantly, remembering his past with such clarity it's like going to the movies. The previous afternoon, while on the phone half-listening to an important client, he'd gone back to the age of six, reliving a mysterious formal lunch in a country house where he'd asked for more strawberries, please. The client had undoubtedly thought he was making silent decisions. Neither does his wife know the extent of his daydreaming, putting it down to worry about the market, or perhaps, in her most fearful moments, to simple withdrawal after a hard marriage of sixteen years."

There's much in these stories about "hard" marriages, as various protagonists look back into their pasts at marriages that failed. These are not the brutal, searing failures one might expect from an author in whose work there is often an undercurrent of violence, but failures of fate, will and luck: marriages that weren't quite right, puzzles in which all the pieces didn't exactly fit and that eventually fell apart. But to call them failures is not precisely right because they produced children, and to Conroy "the children are the point," the beings who give meaning to life and maintain the essential connections between oneself and others.

CONNECTIONS, in fact, are central to Conroy's work. In Stop-Time the connections often are absent, or unclear, and much of the younger writer's energy is concentrated on discovering and strengthening them. In Midair, by contrast, the connections are evident, and he celebrates them even when, as in broken marriages, they cannot hold. As he writes at the end of one story, "What mattered was that everyone was connected in a web, that pain was part of the web, and yet despite it, people loved one another. That's what you found out when you got older, he said."

Nowhere does Conroy examine this theme more effectively and surprisingly than in the title story. At first glance it seems a tale of disconnection: a crazed father escapes from a mental institution and subjects his two young children to a wild, terrifying experience, one that haunts the boy's subconscious until well into adulthood. But the point of the story is not the father's inexplicable actions, but the love -- distorted, lunatic love, to be sure, but love all the same -- that lay underneath his madness and the mysterious way in which what he did to his son came, many years later, to afford that son a kind of liberation. Between the original terror and the final release, the son marries, has his own children and divorces -- all of them connections, just as his past connects to his present when, at the end, he suddenly recalls that long-ago moment of terror.

Quite simply, what Conroy says over and again is that we're all in this together, and that being the case we do best to make the most of it, to find as much as we can in others and in so doing to discover how much there is in ourselves. All of this comes together handsomely in the final story, "The Sense of the Meeting," in which a father has a reunion with two old and treasured friends, then goes off to watch his son play in a college basketball game. Though the resolution of the story strikes me as a trifle on the contrived and sentimental side, what is more important is that Conroy brings father and son together in subtle, revealing ways, ending with each learning important things about the other and about himself.

Conroy is at his best writing about families and ordinary life; the three stories in which he ventures away from these preoccupations, "The Mysterious Case of R," "Roses" and "Transit," are intelligent and interesting but not as affecting as those that arise, however indirectly, from his own life. There's always the threat of narcissism in such strongly autobiographical work, but Conroy avoids it because he has an ample supply of self-mockery and because he is so genuinely interested in other people; he seeks not merely to discover himself, as too many autobiographers do, but to discover the world. Midair is a more slender effort at that than was Stop-Time, but it continues the process in a most rewarding way; further, like Stop- Time it is distinguished by prose that, by telling no more than is absolutely necessary, tells very much indeed.