I might have become a millionaire,” he once said, “but I chose to become a tramp.” As a boy in Scotland, he had thrilled to descriptions of primeval America, to John James Audubon’s picture of passenger pigeons that “darkened the sky like clouds”; and fifteen years later in Wisconsin, on a March morning when the wild geese were heading north on the first warm wind, he said good-by to his family atid wandered away. He wanted to experience the wilderness, “not as a mere sport or plaything excursion, but to find the Law that governs the relations … between human beings and Nature.” It was a quest that lasted all his life.

In the manner of other families, John Muir’s tried to persuade him to go into business, to marry, to settle down, but he had already concluded that “civilization has not much to brag about,” and he wanted none of it. On his first wander, when he was twenty-five, he settled into a pattern he would follow for years: he took a “planless route,” preferring to whirl “like a leaf in every eddy, dance compliance to any wind.” He walked, it was said, with a stride like an Indian’s, moving quietly and swiftly, his eyes on the ground so that he would miss nothing, pausing now and again to examine a rock or an unknown flower through his glass. He was a natural climber (one friend said he moved up mountains like a human spider) and seldom halted until he reached the top. Totally unafraid—of danger, of loneliness, or of death—he never carried a gun, and usually he went for the better part of a day without food; the great staple of his diet was hard, thick-crusted bread, or oatmeal cooked in little cakes on the stones of his campfire, with some tea (all he had to do to get ready for an expedition, Muir said, was to “throw some tea and bread in an old sack and jump over the back fence”). He especially loved swamps—his Highland blood flowed bogward, he believed. And as he hiked, observing everything, contemplating the history of mankind along with the wilderness, he realized that to disturb the balance of nature was to produce flood or drought, as to upset the balance of human society was to produce war. The only course to follow, he concluded, was the universal law of cooperation.

Between these early rambles, John Muir drifted from one job to another, picking up enough money to enable him to travel again or to study, and leaving behind, wherever he paused, a trail of ingenious inventions and laborsaving devices. Even before he left home, he had built, with a few coarse tools brought from Scotland, a small sawmill with a double rotary saw; a “field thermometer” that could be read from nearby pastures, so sensitive that it recorded the slight changes in temperature caused when a person approached within a few feet