When Robert Thorson looks at a lake, he does not see the same things you see. This summer, when he stopped at Lake Calhoun midway along his cross-country journey from Maine to Montana, the writer and geologist looked past all the Lycra and milfoil and saw the sky-blue waters that enchanted Henry David Thoreau when he visited Minnesota more than a century ago.
Calhoun, like many Minnesota lakes, is a kettle lake, a special species of glacial depression that “formed when a block of ice became stranded and partially buried with sand and gravel before melting,” explains Thorson, whose new book, “Beyond Walden: The Hidden History of America’s Kettle Lakes and Ponds,” is a terrific geology lesson soaked in literary history.
The most famous kettle lake is Walden Pond, in Concord, Mass., where Thoreau lived for two years and gathered the thoughts that became “Walden.” Without the lake, says Thorson, there would not have been the book, and without the book, history, the conservation movement, and American literature would not have been the same.
“Despite its complexity, ‘Walden’ was the pivotal work of Transcendentalism, which added the heart part — the spiritual side — to thinking about real, and in some cases raw, nature, not the ‘scenic’ nature of the English Romantic Poets,” he says. “Earlier [authors], like James Fenimore Cooper, for example, saw nature as a powerful, sometimes sinister force, yet one that had to be dealt with to be America. Thoreau saw it as something that should be revered, and in a very potent way.”
And the lake, not just its presence, but its character, was essential. “The chemical purity, surface stillness, hydrological self-reliance, and seasonal moodiness of its water — all characteristic of kettles — contributed importantly to the development of Transcendentalist thinking, particularly with respect to light and air,” he says.
On July 1, Thorson visited Walden Pond and bottled a few ounces of its water, intending to pour it into Lake Wobegon, the second-most famous archetypal American lake. The moment is documented on “Walden to Wobegon,” where the “hydrosphere meets the blogosphere” and where Thorson chronicles his visits to various lakes, literary sites, and roadside attractions, and his extended stay in Minnesota; he grew up in Bemidji, and returns every year to spend time at his family’s lake place in northwestern Minnesota.
When he’s not kettle-hopping, Thorson is a professor of geology at the University of Connecticut. And he doesn’t just love lakes (and Thoreau) — he’s also an admirer of rock walls (and thus, Robert Frost). His first two books are “Stone by Stone,” and “Exploring Rock Walls.”
As for that Walden water? Of course, Garrison Keillor’s lake is fictional, so on July 13, Thorson poured it into Middle Spunk Lake in Avon instead, which he deemed suitably Wobegonic. “Of course, I filtered the water first, so as to serve as good model for preventing the transport of invasive species.”