What’s So Bad About the Badlands? - Don't Know Much About Geography - page 67

1762 English clockmaker John Harrison's No. 4 Marine Chronometer accurately keeps time at sea,
ending a long scientific treasure hunt. A clock that is unaffected by temperature, ship's motion, or
changes in gravitational forces, it was a landmark in the history of navigation, allowing sailors to
precisely determine their longitude, instead of depending on the unreliable and unsafe method of
dead reckoning.
1764 A survey of Pennsylvania and Maryland is begun by British surveyors Charles Mason and
Jeremiah Dixon. It eventually produces the Mason-Dixon line, which later effectively divides north-
ern and southern states.
1768-71 Captain Cook makes the first of three voyages to the Pacific. The second took place
between 1772 and 1775. The third, during which Cook was killed in Hawaii, lasted from 1777 to
1779.
1782 Working for the British East India Company, James Rennell produces the first edition of his
Map of Hindoostan , the first scientifically accurate map of India.
1787 Triangulation across the English Channel links surveys of Britain and France.
1791 Beginning of the British Ordnance Survey, the British government's official arm for mapping
the entire country.
1792-94 British explorer George Vancouver (1758-98) surveys and maps the northwestern coast of
North America. He sails a hundred miles up the Columbia River (as far as the site of present-day
Portland, Oregon). The Columbia was named earlier by American captain Robert Gray. These two
expeditions established competing British and American claims to the territory that went unsettled
until the mid-nineteenth century.
1792-93 Scottish explorer Alexander Mackenzie completes a transcontinental passage across
Canada, becoming the first European to cross the Rockies to the Pacific.
1793 The French Carte de Cassini , the first scientifically conducted national survey, is completed.
1802 The Great Trigonometrical Survey of India is begun, a project that will last for nearly a hun-
dred years, culminating in the mapping of the Himalayas. In August 1913, British and Russian sur-
vey parties meet in Kashmir to link their separate surveys of Central Asia.
1803 The Louisiana Purchase. For $15 million, about two cents an acre, President Thomas Jefferson
more than doubles the size of the United States by purchasing France's holdings in North America
from Napoleon. The French emperor had been frustrated in an attempt to retake Haiti from the
former slaves who had revolted and set up a republic there. Unsuccessful against the former slaves,
the French army sent to retake the island also succumbed to yellow fever, frustrating Napoleon's
designs on North America. Short on cash with which to continue fighting in Europe, Napoleon
agreed to the sale of the massive French territory.