Henry David Thoreau’s Kalendar: Charts and Observations of Natural Phenomena

by Kristen Case

An immersive, beautifully illustrated revelation of Henry David Thoreau’s final project—a monthly almanac of natural phenomena.

In the last years of his life, Henry David Thoreau created something new. Part blueprint for a major new work, part scientific chart, and part re-envisioning of the way we experience the passage of time, Thoreau’s Kalendar was more a tool than a text. Comprised of six multipage charts of “general phenomena,” the Kalendar was an instrument for recording not just natural and weather-related phenomena, but also the hidden relations among them—between the skies of one June and the skies of past and future Junes—relations we often feel but can’t quite hold, rooted as we typically are in our own brief moment of linear time. 

Combining reproductions of Thoreau’s hand-drawn charts with transcriptions of the Kalendar’s text and essays by acclaimed poet and scholar Kristen Case, this gorgeously crafted volume illuminates the final project of one of America’s most treasured writers and naturalists and offers a timeless, transformative vision of how to live harmoniously with the living world around us.

Genres: Nonfiction

224 pages, Hardcover

Published November 11, 2025

Reviews

[Jerry Edward Stephens · Rating 5 out of 5]

Many readers know of Henry David Thoreau and the story of Walden Pond. Fewer may know of his radical ideas and social thinking. They may understand that his books often addressed his thoughts about simple living and civil disobedience. Even fewer readers may understand that Thoreau may also be known for his naturist observations and his strong feelings for the natural world he lived in. These observations of the weather and other natural events arose from his regular stays at Walden Pond near Concord, Massachusetts. Along with the reams of literature and political and social commentary, Thoreau also recorded many references to weather and other natural phenomena and were included in his anticipated work known as the Kalendar, maintained by Thoreau between 1860 and 1862. Now Kristen Case, a poet and literary scholar in Maine, has reproduced his naturist observations with a publisher experienced in publishing digital images. Case is now the Executive Director of the Monson Seminar affiliated with the University of Southern Maine. The published book consists of large images of the manuscript with Case’s interpretation corresponding to the relevant text by Thoreau. Case takes great pain in describing how she first learned of Thoreau’s notes about seasonal change occurring near Concord. The original literary interest culminated in the creation of a digital archive at the Kalendar Project to be found at https://thoreauskalendar.org/about.html. This work ended with Thoreau’s death in 1862. Why Thoreau maintained these observations is open to great conjecture. Much remains unknown about Thoreau’s ideas for these observations. There are hints that they may be closely related to Thoreau’s ideas about simple living in perfectly natural environments. This book is a very attractive reproduction of Thoreau’s original notebook. It is, as one caution, difficult to read or decipher just what Trump was writing. This very attractive book should appeal to those who truly appreciate Henry David Thoreau’s ideas and writing. It should also appeal to readers who appreciate the pragmatic ideas that arose frequently throughout American history. It may only appeal to collectors of books with included quality reproductions. In any event, this book is highly recommended for most readers.