After President Jefferson purchased the Louisiana Territory from Napoleon in 1803, he sent out an exploratory expedition to the new land, headed by two army captains, Jefferson's secretary Meriwether Lewis and his friend William Clark. The two were to go as far as the Pacific Ocean, seeking among other things an easy "northwestern passage" across the continent.

      The two set out from St. Louis in the spring of 1804 with about 40 men. A year and a half later, after remarkable adventures, the bulk of their "Discovery Corps" (some, as planned, had returned early) reached the Pacific shore. That included York, Clark's black slave who became popular with the Indians (some rubbed his skin to check if the color came off), one-eyed Cruzatte who entertained the explorers with his violin and even a Newfoundland dog, probably named Scannon. Three members had joined the explorers during their winter encampment among the Mandan Indians--the Frenchman Charbonneau, the 17-year old Indian woman Sacagawea who was captured by the Indians from the Shoshoni tribe and sold to Charbonneau, and their infant son born that same winter. Charbonneau named him Jean Baptiste, but Clark called him Little Pomp.

      One hundred and eighty years later Dayton Duncan, a young American, retraced the explorers' trail in a Volkswagen camper, and this book is his account. It is a personal tale, informal and eminently readable, shuttling back and forth between the two parallel threads of the author's journey and that of Lewis and Clark. Like his predecessors, Dayton is an explorer, seeking the measure of the American West, the things that set it apart, wondering what had changed since the days of Lewis and Clark and what has remained constant.

      It is not the west of the parks and mountains which tourists like to visit, but the big-sky empty expanses of Montana, the struggling farmers and dying towns of the Dakotas, the settlers and the Indians, the conservationists and developers, and the historical conflict between them. He talks to old-timers, meets modern custodians of history, experiences a bitter wintry night in a reconstructed Indian sod-house, participates in a buffalo hunt (of sorts) and spends time with both cowboys and Indians.

      It is not great literature but an intimate travelogue, told with humor and complete with "rules of the road" which Duncan makes up as he goes along. He also comes up with two "rules of the trail." After his sure-footed horse carries him safely back to base, over narrow mountain trails on a dark night, he formulates "trail rule #1," namely, "Trust your horse." A bit later, after Duncan is tossed by a spooked horse racing through a forest, he comes up with "trail rule #2" which is "Never trust your horse."

      Again and again the story shifts two centuries back, to the "Discovery Corps" traversing the same terrain. The tidbits from the explorers' accounts, especially from Lewis' journal (complete with his random spelling) make one want to read more of it. Just after first crossing the continental divide, Lewis marked his 31st birthday in these words:

      "This day I completed my thirty first year, and conceived that I had in all human probability now existed about half the period which I am to remain in this Sublunary world. I reflected that I had as yet done but little, very little, indeed, to further the hapiness of the human race or to advance the information of the succeeding generation. I viewed with regret the many hours I have spent in indolence, and now soarly feel the want of that information which those hours would have given me had they been judiciously expended, but since they are past and cannot be recalled, I dash from me the gloomy thought, and resolved in future, to redouble my exertions and at least indeavour to promote those two primary objects of human existence, by giving them the aid of that portion of talents which nature and fortune have bestoed on me; or in future, to live for mankind, as I have heretofore lived for myself."

      Actually Lewis lived only four more years, dying mysteriously in an inn on the Natchez trace, apparently a suicide--perhaps, as some modern scholars have speculated, despondent over the venereal disease he had picked up among the Indians. The corps itself returned in 1807, having lost just one man, probably to a burst appendix. York was given his freedom and disappeared from history. Two members who returned to the rich trapping grounds of western Montana were scalped by Indians, while a third, Colter, escaped from them stark naked and brought back the first stories of the Yellowstone country. Sacagawea (historians say it should be pronounced "Sakakawea," bird woman) apparently died young, though an imaginative historical novel had her live to 1884; but "Little Pomp" was educated by Clark in St. Louis, toured Europe, participated in the California gold rush and ended his days in Oregon in 1866.

      And as for Dayton Duncan's adventure, I'm not telling any more. Read the book.