John Wesley Powell(1834--1902)Was a famous explorer of the American West.When he Was young,his mother put him under the guidance of George Crookham,a self-taught scientist,from whom he received a wide,but informal,education.Young John learned many things about the natural sciences.But his father preferred him to study religion.The argument continued for three years.Then John decided to leave home to seek further education.He soon discovered that he knew more about science than any teacher he met.He realized that the only good scientific education in the country came from colleges in the east,like Harvard and Yale.But he Was too poor to go to them,SO he got work as a school teacher in Illinois.Whenever possible,he went on scientific trips of his own.    In 1861,civil war broke out in the United States.John joined the Union forces of the North.At the battle of Shiloh Powell lost his right arm.Despite his disability, he began his famous exploration of the Colorado River on May 24 1869. It Was one of the greatest trips of discovery in the history of America.Never before had any white men traveled to that area.The trip Was far more dangerous than expected.The rivers were filled with rocky areas and waterfalls.Sometimes,the boats overturned or broke into pieces against big rocks.All along the way, Powell measured distances,temperatures,heights,depths and currents.He examined soils,rocks and plant life.Powell'S explorations led to the creation of US Geological Survey, which became responsible for all mapping and scientific programs of American lands. Powell's scientific studies of western lands shaped his ideas of how those lands should be used.He suggested programs to control both crop farming and cattle raising.He Was especially concerned about water supplies.Many of his ideas were rejected at first and were not signed into law until years after his death because they were far ahead of his time. From the text we can see that  _  .
Harvard  University gave Powell much support for his exploration John was the first American to travel to the Colorado River most of Powell'S ideas were signed into law before he died Powell'S explorations caused the creation of US Geological Survey