Henry David Thoreau&#8217;s journal was his life&#8217;s work: the daily practice that accompanied his daily walks; the source from which he drew his books and essays; and perhaps the most searching investigation ever made into the everyday environment, seasonal changes, and the ecology or interrelations among different facets of nature and the moods and mind of the observer. It is a treasure trove of some of the finest prose in English and is deeply beloved by its readers&#8211;but at roughly two million surviving words, or 7,000 pages, it is not often read.<br><br>This reader&#8217;s edition, commissioned specially for New York Review Books, is the largest one-volume edition of the <i>Journals </i>ever published. It draws on the entirety of the <i>Journals </i>: rather than collecting highlights out of context, it captures the scope, dailiness, rhythms, and variety of the work as a whole. Thoreau&#8217;s infinitely curious mind ranges over nearly every phenomenon of nature and life in nineteenth-century New England&#8211;the <i>Journals </i>are a rich source of social, environmental, natural, and cultural history&#8211;but he looks inward as well as outward, for &#8220;It is in vain to write on the seasons unless you have the seasons in you.&#8221;