It was in 1745 that Washington's school-days came to an end. His share of
his father's property being his mother's till he was twenty-one, a
livelihood had to be found, and so at about fourteen years of age the work
of life began. Like a true boy, the lad wanted to go to sea, despite his
uncle's warning "that I think he had better be put apprentice to a tinker;
for a common sailor before the mast has by no means the liberty of the
subject; for they will press him from a ship where he has fifty shillings
a month; and make him take twenty-three, and cut and slash, and use him
like a negro, or rather like a dog." His mother, however, would not
consent, and to this was due his becoming a surveyor.

From his "Young Man's Companion" Washington had already learned the use of
Gunter's rule and how it should be used in surveying, and to complete his
knowledge he seems to have taken lessons of the licensed surveyor of
Westmoreland County, James Genn, for transcripts of some of the surveys
drawn by Genn still exist in the handwriting of his pupil. This implied a
distinct and very valuable addition to his knowledge, and a large number
of his surveys still extant are marvels of neatness and careful drawing.
As a profession it was followed for only four years (1747-1751), but all
through life he often used his knowledge in measuring or platting his own
property. Far more important is the service it was to him in public life.
In 1755 he sent to Braddock's secretary a map of the "back country," and
to the governor of Virginia plans of two forts. During the Revolution it
helped him not merely in the study of maps, but also in the facility it
gave him to take in the topographical features of the country. Very
largely, too, was the selection of the admirable site for the capital due
to his supervising: all the plans for the city were submitted to him,
and nowhere do the good sense and balance of the man appear to better
advantage than in his correspondence with the Federal city commissioners.