In 1972 Kathryn Lasky, a decidedly unathletic writer ""from [a] short line of recently arrived Russian and Polish Jews,"" wed Chris Knight, a dauntless, world-roaming photographer born of generations of Maine sailors. Up in a single-engine plane, Chris proposed to give up flying--Kathryn was wondering why he hadn't married a rugged and fearless Other--if she would sail across the Atlantic with him. This, then, is only secondarily the story of their two Atlantic crossings, of the intervening cruises along Scandinavian shores and through European canals. Primarily, it's Kathryn's bemused, ingratiating account of discovering a seaworthy, if not sea-kindly, identity of her own--having ""nothing to do with the prefab cheerfulness, stiff-upper lip, gung-ho qualities that are too often associated with contests of endurance and courage."" On their honeymoon, she went up the mast to repair the halyard, ""dangling thirty-five feet in the air,"" only because she didn't trust herself to haul Chris up without panicking. (""The decision was essentially one of rational cowardice."") And what really got her across the Atlantic, you might believe, was her ""Pepperidge Farm strategy""--a bag of Bordeaux until a certain longitude, then a stretch of ""voluptuous and delicate"" Mint Milanos, then a switch to one of the ""earthy and crunchy"" Old-Fashioned line. (They stayed crisp in Tupperware--after Kathryn, stymied by a Tupperware rep, asked if Sir Francis Chichester had had to go to a Tupperware party to get his supply.) Interspersed with the rigors and perils of the crossing are ""landlocked"" recollections of a grandmother's domestic flair and ""obsessive dreams of gardens."" (Her reading, too, runs to Gourmet and Jane Austen.) Cruising in European waters brings delighted discovery of Norway and Norwegians, a certain wariness of things German, atmospheric notes on passage through Holland, canal ""calisthenics"" crossing France. The south Atlantic return isn't the promised piece-of-cake--""I continued in fine style a two-thousand year tradition of persecution that was literally pounded into me."" And even on a ""civilized"" cruise to Martha's Vineyard and Nantucket, Lasky doesn't proclaim herself a devotee. But she does take pleasure in son Max's precocious seafaring prowess--and attributes the ""buoyancy"" of her marriage to its oceangoing baptism. Considerable spirit and charm--with a minimum of attitudinizing or straining for comic effect.