During the late 1840s and the 1850s, Thoreau made a number of excursions beyond Concord — to Maine (first visited by Thoreau in 1846, while he lived at Walden) in 1853 and 1857; to Cape Cod in 1849, 1850, 1855, and 1857; to Quebec in 1850; to Mount Monadnock in southern New Hampshire (which he visited repeatedly over the years) in 1852 and 1858; and to the White Mountains (to which he first journeyed in 1839 with his brother John) in 1858. In July of 1850, Thoreau made a somber trip to Fire Island, off New York, to search for the body of Margaret Fuller, who had died in a shipwreck on her return to America with her Italian husband and their young child. Thoreau sometimes took companions when he traveled, among them Ellery Channing and Edward Sherman Hoar. His journeys provided the raw material for several posthumously published books — The Maine Woods (1864), Cape Cod (1865), and A Yankee in Canada (1866).
Thoreau's trips to Maine afforded him the chance to observe Native Americans. Since boyhood, Thoreau had been fascinated by Indians. There were Indians in Concord even in the 1850s, but their culture had long since lost its integrity. In Maine, Indians were still to a degree able to live "free and unconstrained in Nature." Thoreau used Indian guides on his Maine trips in order to learn what he could of their wisdom and their ways. He wrote about Joe Polis, his guide in 1857, in The Maine Woods. In Concord, Thoreau was a collector of arrowheads and other artifacts, highly skilled at finding them in places where others never suspected they might lay. He also kept volumes of research notes on the Indians, intending but ultimately unable to write a book on the subject.
For seven years after Thoreau's return from Walden Pond in 1847, he worked and reworked his material about his sojourn there, extensively and repeatedly revising what he had produced. The book was published in August of 1854 by the Boston company of Ticknor and Fields, publishers of a number of major authors of the American Renaissance. Walden was more widely and better reviewed than A Week on the Concord and Merrimack Rivers had been, and it sold well.
