Times Three

Science fiction Grand Master Silverberg explores the possibilities and pitfalls of time travel in this omnibus of three classic novels. In 1968's "Hawksbill Station," the government has found a novel way to dispose of malcontents: just send them to the late Cambrian era. Next is the wry "Up the Line" (1969), wherein a highly trained Time Courier falls in love in ancient Byzantium. Despite a slow opening, the novel effectively captures the decadence of both past and present, as well as the wrench of responsibilities that tug in both directions. 1987's "Project Pendulum" pushes Einstein's twin paradox to the breaking point and is the tightest, most sophisticated, and darkest of the three. These novels showcase not only the astounding challenges of time travel but the growth of a talented writer whose ideas and characters continue to entertain. (Apr.)