SERIOUS WRITERS MUST nearly always compromise between the selfish demands of art and the human comforts of marriage and family. Notwithstanding, spouse and children - those classic "hostages to fortune" - may also be the most insidious of the Enemies of Promise. As J.R. Humphrey's Subway to Samarkand demonstrates, few battles can be so quietly devastating as that between the Angels in the House and the Muse. In a manner reminiscent of Randall Jarrell's Pictures from an Institution and Frederick Exley's A Fan's Notes, Humphrey's rather elegiac novel depicts the accumulated effects of love and unrealized ambition upon a cross-section of artistic men and women.

The central action of the book focuses on a year in the life of Jack Fross: "self-centered, erotic, blocked writer, henpecked husband, rejected father, incorrigible cheat, penny pincher, dreamer, loser, girlwatcher, moviedrugged nosepicker." Despite this self-description, Jack is no wild Ginger Man: a middle-aged romantic, he achingly dreams of the adventure and exoticism associated with Tamerlane's ancient capital, Samarkand.

Jack's world, however, overflows not with fabled romance, but with assorted characters of death and blight: the university where he teaches writing is in financial straits, garbage piling up in its corridors; his neighborhood has grown increasingly dangerous; his friends are selling out, cracking up, or committing suicide; he hasn't written a novel in 18 years; his diseased vocal cords prevent him from speaking above a rasping whisper; despair is all around him. Yet Jack clings to his dream of infinite possibility, of Baudelairean "luxe, calme, et volupte." As his young mistress Gail asserts, he is a dreamer's dreamer. Caught between his instinct to travel to Samarkand and his sense of obligation to a wife he once cared for and a grown daughter he still loves, Jack persists irresolutely in what he calls "safe adventures" - nights with Gail, purple pageants in his notebooks, rambling talks with a series of memorable buddies.

Whether divorced, married, or unhappily single, each of Jack's artist cronies has been striken by marriage. Fletch proclaims that marriage is a trap and ends by having 14 children; Paul, because of his wife's support, spends his entire life on a 1200-page outline for a novel about "feebs and idiots" living somewhere in the desert of the Southwest; Sean Sleeps constantly and morosely credits Fig Newtons with having saved him from remarriage; Norman, like his frayed coat, is slowly unravelling from the wear and tear of suburban life.

If the men of Subway to Samarkand are dependent, sentimental, and easy bruised, the women who dominate their thoughts and lives re realistic and durable. Ancient bookclub novelist Dorothy Dole rises from her death bed, reborn, vigorous, lusty, she plants a deep tongue-seeking kiss on a surprised Jack. When Sam's paintings fail to sell, he collapses; but his wife Martha venture forth and becomes a sought-after fashion photographer. After her divorce, Gail vows never to be satisfied with one man again and fiercely dedicates herself to acting and singing. Even Janice and Perse, Jack's wife and daughter, are tough, sensible women, icily protective of hearth and home. Perfectly conventional, the two have no sympathy for Jack's still vaulting ambitious to write another novel and to travel the Golden Road to Samarkand. As Janice says, Jack and his friends all need to "shape up."

Perhaps she is right, for Humphreys leaves us oddly perplexed about the men in his book. The implication is strong that better, truer artists would not have caved in so easily or so much.

Though sensitive and likeable, even Jack remains indecisive, sufficiently content to muddle along, a homebody tied to strong women. When confronted by the swift, sudden turn ofn possible death by cancer of the vocal cords, his life scarcely changes. He is curiously passive as the weeks of radiotherapy and recovery go by. Only in the last pages of Subway to Samarkand does Jack finally act - to his surprise and the reader's delight.