Powell was a civil war officer who later took a teaching position at Illinois Normal University. He was by nature an explorer and spent considerable time tramping the upper Midwest. In the summer of 1867, he and some of his students made a field trip to the headwaters and tributaries of the Green River. Intrigued with the country, he returned in 1868, wintered there, and decided to mount an expedition to explore the course and navigability of the river. On May 24, 1869, Major Powell and a small band of men launched four boats to begin what would be a 99-day expedition from known territory in Wyoming to known territory in Nevada. Between the two settlements lay some 1000 miles of what Powell called "the Great Unknown." He and his men basically had to invent expedition river running. The boats, stout and heavy, were off-the-shelf navy longboats with sharp cutwaters, meant to be rowed bow-first on the sea rather than down rock-studded rivers. Powell's discovery run, fraught with excitement and tragedy, proved that the river originating in northwest Wyoming was the same river that ended in the Gulf of California, that it went through the Grand Canyon, and that it could be traveled by boat. As they came down the river they took periodic observations of latitude and longitude, elevations, and estimates of distance that allowed mapmakers to show the river's course. In 1871-1872 Powell led a second expedition over most of the same route. Several accounts of the expeditions were published in government documents and popular publications of the time and were read avidly by those who planned to try the river later.
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Descrizione libro Promontory Press, 1972. Hardcover. Condizione libro: New. Codice libro della libreria P110883940124