Thoreau spends many winter evenings alone beside his fire, while the snow whirls violently outside his house. He is able to dig a path to town through the deep snow, but has few visitors to his neck of the woods in this cold season. Alone in the wilderness, Thoreau finds himself compelled to conjure up images of those who had endured the hard Walden winters before him.

Although the route between Concord and Lincoln is sparsely populated, Thoreau believes it had been settled more thickly earlier in the century. Many of the earlier inhabitants had been blacks: Thoreau summons up images of Cato Ingraham, the spinster Zilpha, Brister Freeman and his wife, Fenda. Some of their abodes have almost completely vanished, destroyed by age or fire. Thoreau recalls how Breed’s hut burned to the ground in a fire twelve years before. Thoreau and the local fire brigade had rushed out to save it, but had found it too far gone. Thoreau recalls seeing the heir to the house lying in shock, muttering to himself about the loss of his property. Near Lincoln, a potter named Wyman had once squatted, followed by his descendants. Another memorable recent inhabitant of the woods was an Irishman named Hugh Quoil, formerly a soldier at the Battle of Waterloo, who had come to live at the Wyman place. All these old-timers are now gone, and Thoreau lives alone amid the ravaged foundations and empty cellar holes that once marked their homes. The site of a once burgeoning village is, by Thoreau’s time, marked only by decay, and by grasses and lilacs planted in more prosperous times and outliving their planters. Thoreau muses on the insignificance and transience of humankind’s place in nature.

Thoreau has sparse contact with other humans in the depths of winter, and even animals keep to themselves at times. Among Thoreau’s most reliable companions are the barred owl, an occasional woodchopper, and his friends William Ellery Channing and the philosopher Amos Bronson Alcott. Thoreau’s mentor and benefactor, Ralph Waldo Emerson, also comes. None of these men is directly named in the text, however. Emerson is identified as the “Old Immortal.” Thoreau keeps regular watch for “the Visitor who never comes,” conforming to an ancient Hindu law of hospitality.

Walking over a frozen pond, Thoreau finds everything more open and spacious, with wide yards for sliding and skating on the frozen surface. On these days, the air is filled with the call of the hoot owl and the cry of the goose resounding through the woods. In the morning the red squirrels scuttle and scavenge, at dusk the rabbits come for their feedings, and on moonlit nights the foxes search the snow for prey. Such sounds come and go, but the sounds of snow falling and ice cracking continue through the day and the night. Thoreau places the harvest’s unripe corn at his doorstep, attracting smaller squirrels and rabbits to feed near his dwelling. Sometimes he sits and watches the little creatures paw at their food for hours. At other times they carry their bounty away into the forest, discarding their refuse in various spots. This refuse attracts the jays, chickadees, and sparrows that descend upon the leftover cobs and pick at them. On certain mornings and afternoons, Thoreau hears hounds yelping in pursuit of their quarry. Thoreau often talks with the huntsmen who pass by Walden.

Thoreau’s first task on waking up is to collect water for the day. In the winter this job proves difficult, as he has to chop through the ice. He is soon joined by a hardy group of fisherman. Thoreau is amused by their primitive methods, but is more amazed by what they catch, notably the distinctively colored pickerel, which stands out from the more typically celebrated cod and haddock of the sea.

In an effort to measure the depth of Walden Pond and dispel the myth that it is bottomless, Thoreau uses a fishing line and a light stone. Many locals believe the pond to be bottomless, but Thoreau measures it at just over one hundred feet. Thoreau meditates on the way people wish to believe in a symbol of heaven and infinity. Through repeated soundings, Thoreau is able to get a general sense of the shape of Walden Pond’s bottom, and learns that it conforms to the surrounding terrain. The pond reaches its greatest depth at the point of its greatest length and breadth. Thoreau wonders if this might be a clue to pinpointing the deepest points of larger bodies of water, such as oceans. To test this hypothesis, Thoreau plumbs the nearby White Pond. Again, the point of greatest depth is quite near to the point where the axis of greatest length intersects the axis of greatest breadth. Having more evidence to bolster his theory, Thoreau extends it to a metaphorical level, supposing that a person’s behavior and circumstances will determine the depths of his or her soul.

In Thoreau’s second winter at the pond, a team of one hundred men and more arrives at Walden Pond. Acting as agents for an ambitious farmer, these workmen cut and cut at the ice over a period of two weeks, claiming they could harvest as much as a thousand tons on a good day and ten thousand tons over the whole winter. It is a complex business, on a grand scale, and the result is a great heap of ice to be stored and later sold for a profit. Although some of it reaches far-off destinations, Thoreau notes that the greater part of it melts and returns to the pond.

These three chapters are dominated by winter, a time for stepping back from outside work and withdrawing to the inner world of home and mind. As a result, this portion of Walden is brooding and highly meditative, focusing on ideas of absence, history, and infinity. “Former Inhabitants; and Winter Visitors “ is a survey of Walden’s ghosts, or at least of earlier residents of the pond who are “conjured up,” as Thoreau says, in his own mind. Prominent among the dead he conjures up from the graves of history are black people: Cato Ingraham, Zilpha, and Brister Freeman are all poor blacks who are alive no longer, but still live in Thoreau’s personal memory. Given Thoreau’s strong opposition to Southern slavery and his proven commitment to aiding fugitive slaves, his reminiscences of black people here take on an ideological importance. We sense that Thoreau is recalling them because the nation’s official chronicles do not: in a generally racist country, individuals must provide a humane commemoration for those who are otherwise overlooked and forgotten.

The absent black people segue in Thoreau’s imagination to another absence: that of the hut that had once belonged to Breed before it burned down a dozen years earlier. This story of a mere house takes on a symbolic meaning. As Thoreau narrates the story of how he and the other local fire volunteer firefighters rushed to save the hut, only to decide “to let it burn, it was so far gone and so worthless,” our thoughts turn to the inevitable end to all things, houses and people alike. The moral is that it is useless to struggle to preserve them, for destruction will come regardless of our efforts. Thoreau says of the deceased Irishman, Hugh Quoil, that “[a]ll I know of him is tragic,” and the same could be said of almost everything he mentions in these wintry and death-obsessed chapters. His focus on the mortality of all life has a biblical feeling, as in the theme of memento mori (Latin for “remember you shall die”) common in New England Protestant sermons and prayer books. When Thoreau mentions scripture in this chapter, his words sound even more religious. The theological opposite of all this mortality is, of course, immortal heaven. Thoreau again equates heaven on earth with water, like that of Walden Pond or Breed’s well, “which, thank Heaven, could never be burned.” Water is the only thing impervious to the fires of death, and so there are spots of immortality even amid these ruins of destruction. When Thoreau later dubs his occasional visitor Emerson an “Old Immortal,” we feel that philosophy is another such spot, and that the water’s eternity is connected to the eternal truths glimpsed by great minds.

The idea of eternity is deeply sounded in the chapter “The Pond in Winter,” which focuses on the question of whether Walden Pond is, as people rumor it to be, infinite. Thoreau is determined to measure its depths, just as he reaches into the depths of himself in his backwoods retirement. The newly fallen snow makes the pond hard to locate, and the result is suggestive: the purity within us could be anywhere, if we can pierce the surface of our earthly lives. When Thoreau finds Walden Pond, cuts through the icy layer on top, and gazes into the “perennial waveless serenity” within, his conclusions are theological rather than natural, or both at once. “Heaven,” he says, “is under our feet as well as over our heads.” Thoreau seems satisfied that the pond should be seen as a bottomless quantity of water descending all the way to the other side of the globe, since it encourages inspirational thoughts of infinity.

We might infer that some men, like Thoreau, do not need symbols of infinity, since they experience infinity directly: the infinity of man’s spirit. Thoreau is content to prove that Walden Pond is only a hundred feet deep, since he knows that real depth is elsewhere, in his own mind and soul. Thoreau compares ice and water to the intellect and the emotions respectively, thus depicting the entire human spirit as composed of different aqueous states: the human is water. He sees a reflection of himself in the cut ice, “a double shadow of myself,” mirrored in the water. Thus every time he goes for a drink of water, he communes with the timeless aspect of his own self. Water becomes a metaphor not just for heaven but also, more important, for the human soul that is itself heavenly, for the divine side of humankind. This divinity can never be depleted, as Thoreau hints in his detailed account of ice cutting, which in the winter of 1846 yields ten thousand tons—most of which melts and flows back ultimately to the pond again, so that “the pond recovered the greater part.” It is the living source, inexhaustible.