Here's another attempt to bridge the gap between the ``two cultures'' of the humanities and the sciences, this time by a mathematician/mystery novelist. In his introductory ``Note to the Reader,'' Berlinski (Less Than Meets the Eye, 1994, etc.) emphasizes that his goal is to provide not a textbook but a ``tour,'' offering the reader the sort of ``Aha!'' insight characteristic of math. To that end, he brings his novelist's equipment to bear on the subject, with well-drawn character portraits of the men who developed calculus (Newton and Leibniz in particular) and dramatic scenes featuring the author as an instructor with a recalcitrant college math class. There are proofs (presented in appendixes to each chapter), but no problems to solve. And the focus of the text is on the meaning and application of the central concepts of the calculus, as in the use of the first derivative to determine the speed of a falling body after a given elapsed time--one of the purposes for which the technique was invented. A reader who remembers algebra can follow most of the proofs, and the history of mathematics is interestingly presented. But the book goes off track in several ways. Berlinski's portrayal of his college calculus class suggests contempt for those who ``don't get'' math; considering how many readers may picture themselves among the author's reluctant students, this is not an asset. Too many sentences force the reader to stop and puzzle out the plain sense of what the author is saying rather than the mathematical point he is trying to illustrate. Minor factual errors intrude: The author attributes Millay's line ``Euclid alone has looked on Beauty bare'' to Keats, then makes a point of Keats's ignorance of math. Finally, the labels on the diagrams often don't correspond to the text they illustrate, a source of potential confusion. A worthy attempt to bring an important scientific concept to the general reader; too bad the execution falls short of the ambition.