X STANDS FOR UNKNOWN

Another collection of columns from The Magazine of Fantasy and Science Fiction: 17 pieces, 1982-83—in the usual amiable, faintly soporific Asimov mold. His first topic is electromagnetic radiation—from Newton's discovery of the visible spectrum, through Maxwell's field equations, to cosmic rays (which are actually particles, not radiation). Next: silicon, an element closely related to carbon, and why there are no silicon lifeforms (the main reason is that silicon compounds are insoluble in water)—although, Asimov notes, computers based on silicon chips may one day challenge this assumption. In the section on astronomy: Halley's comet, due to reappear in 1986, and its historical reputation for foretelling dire events; the idea of the geostationary orbit, invented by Arthur C. Clarke; novas and supernovas; the slow realization, over the last few centuries, that Earth is not the center of the universe or, indeed, of any cosmic importance at all. Also on the agenda: the Fibonacci numerical series and the "golden section" of the ancients; Biblical cosmology; an examination of irrationality-in-general, and irrationality in science. Mildly informative, rather complacent, altogether bland: an average outing overall.