<DIV>Brian Hayes is one of the most accomplished essayists active today—a claim supported not only by his prolific and continuing high-quality output but also by such honors as the National Magazine Award for his commemorative Y2K essay titled “Clock of Ages,” published in the November/December 1999 issue of <I>The Sciences </I>magazine. (The also-rans that year included Tom Wolfe, Verlyn Klinkenborg, and Oliver Sacks.) Hayes's work in this genre has also appeared in such anthologies as <I>The Best American Magazine Writing, The Best American Science and Nature Writing, </I>and <I>The Norton Reader</I>. Here he offers us a selection of his most memorable and accessible pieces—including “Clock of Ages”—embellishing them with an overall, scene-setting preface, reconfigured illustrations, and a refreshingly self-critical “Afterthoughts” section appended to each essay.</DIV>