Convoluted time-travel yarn--a sort of multiple-reality Chinatown--from the author of Arachne (1990), etc. In the year 2496, Zhu Wong, a revolutionary Daughter of Compassion, is arrested for attempted murder, detoxed, then brought before the redhaired Chiron of the Luxon Institute for Superluminal Applications. Chiron proposes to send Zhu back to 1895 San Francisco via ""tachyportation,"" where she is to locate the aurelia, a McGuffin that was/will be presented to Chiron when he visits in 1967. Zhu, with little choice but to accept, is fitted with an advanced computer implant, the Muse. In 1895, she keeps the books of the ""boardinghouse""--i.e., brothel--run by the champagne-swilling Jessie Malone, and becomes infatuated with handsome, well-traveled drunk Daniel Watkins. Zhu fails to locate the aurelia, but does find the young whore Wing Sing, to whose daughter she is supposed to present it. But with every action Zhu takes, reality changes, leaving no aspect of her mission consistent or reliable. And when she does finally obtain the aurelia, she's murdered by Tong enforcers--in one reality; in another, Zhu becomes pregnant and Wing Sing is murdered. Tremendously hardworking, with a heavy emphasis on seamy period detail, but neither the plot nor the time-travel framework adds up--and the present-tense narrative merely compounds the difficulties.