Mr. Furnas has been around a while producing entertaining-to-serious views of historical movements and oddities, and this time he turns to an ingenious time fantasy. Nobly proportioned Imgen Arkwright, wife of a naval officer, descends on the remote island of Tarafu in the Wilkes Archipelage to tend the hearth and sweep, much to the delight of the homesick American personnel stationed on the grubby isle after World War II. Imogen's trip-induced by bare lust rather than locoweed--begins when she is cast adrift on another eeric island with Dr. Moore, a visiting scholar, whose investigations of primitive sex habits made him a lecture favorite. After being assaulted by visions of the native offspring of a seventeenth century seafaring British doctor--the pariah natives all wearing cocked hats and faithfully preserving the grisly chronology of the rhyme ""Solomon Grundy""--the castaways conclude that Time is being fudged up in a stimulating and fascinating manner. Imbibing the local mescaline untangles mysteries and adds others. While Dr. Moore ecstatically witnesses a sacrificial ceremony in the past. Imogen is propelled into the future, but not until she has cracked Dr. Moore across the skull with a religious relic. Well, did she or didn't she? No one really cares since there is little philosophic or allegorical direction. But Mr. Furnas tells a tall tale with spirit and a sense of fun.