David Henry Thoreau was born in Concord, Massachusetts, on July 12, 1817 and spent much of his youth outdoors, enjoying nature and honing his natural ability of observation. After graduating from Harvard College and returning home to Concord, he began calling himself Henry David Thoreau and embarked on a career as a writer and lecturer. Finding it necessary to have other means of making a living, he also worked in his father's Concord pencil factory before starting his own school at the Concord Academy with his brother, John, in 1838. The brothers' interest in surveying led them to a purchase of surveying instruments for the school. When John's health began to fail, Henry closed the Academy and tried to support himself by writing, but again found it necessary to engage in other types of work -- including carpentry, stonemasonry, house painting, and fencing.
In 1845, still sorrowful three years after his brother's death, Henry's good friend Ralph Waldo Emerson offered him the use of his woodlot at Walden Pond as a place to build a house and reside near to nature while continuing to write. Thoreau built a small, comfortable one-room house where he could live simply and near to nature, and devote his time to studying, gardening, and writing. While there, he made the first accurate map of Walden Pond and rekindled his interest in surveying. Although he lived a solitary existence, he regularly entertained guests and began to work in and around Concord as a surveyor.
In his book Walden, Thoreau described himself as a "self-appointed inspector of snow storms and rain storms" and "surveyor of forest paths". Many years later, he described surveying as "a noble employment which brings you within hearing of [the birds]". Over the next sixteen years, he performed over 150 surveys in the Concord area, and was very highly regarded for his attention to detail. He was entrusted by landowners to mark boundary lines in their absence, and to prepare documents for court hearings.
As a naturalist, Thoreau's observations were often more perceptive than those of trained scientists. He published two books during his lifetime, A Week on the Concord and Merrimack Rivers, a story of a trip taken with his brother in 1839, and Walden, a narrative of his experiences from 1845 to 1847 -- a book which encourages and promotes the preservation of our natural environment.