Normally, when one thinks of the expansion of the American West, the event most likely to come to mind is the California Gold Rush of 1849. While that profitable discovery did boost California's population by 80,000 eager prospectors, there remained an awful lot of land between the Pacific Coast and St. Louis, Missouri.
<Tab/>In 1803 President Thomas Jefferson sent a secret message to Congress calling for an expedition into the area west of the Mississippi River to the Pacific Ocean. He felt that an intelligent military man with a dozen hand-picked men could successfully char…