[Footnote 2: The author has evidently not seen Bancroft's "Native Races of the Pacific," an exhaustive work in five volumes, published at New York and San Francisco a few years ago, and which embodies the researches of a number of gentlemen, who collected their information on the spot, and whose contributions to our knowledge of the past and present life of the Indians should certainly not be ignored.--_Trans._] Simultaneously with the discovery of the ruins the flora and geology of the country began to be studied, and in the latter science great surprises were in store for future explorers. It was so important for the American government to proceed rapidly to reconnoitre the vast territories between the United States and the Pacific, that another expedition was speedily sent out. In 1819, the military authorities commissioned Major Long to explore the districts between the Mississippi and the Rocky Mountains, to trace the course of the Missouri and of its principal tributaries, to fix the latitude and longitude of the chief places, to study the ways of the Indian tribes, in fact to describe everything interesting either in the aspect of the country or in its animal, vegetable, and mineral productions. Leaving Pittsburgh on the 5th March, 1819, on board the steamship _Western Engineer_, the expedition arrived in May of the following year at the junction of the Ohio with the Mississippi, and ascended the latter river as far as St. Louis. On the 29th June, the mouth of the Missouri was reached. During the month of July, Mr. Say, who was charged with the zoological observations, made his way by land to Fort Osage, where he was joined by the steamer. Major Long turned his stay at Fort Osage to account by sending a party to examine the districts between the Kansas and the Platte, but this party was attacked, robbed, and compelled to turn back after losing all their horses. After obtaining at Cow Island a reinforcement of fifteen soldiers, the expedition reached Fort Lisa, near Council Bluff, on the 19th September. There it was decided to winter. The Americans suffered greatly from scurvy, and having no medicines to check the terrible disorder, they lost 100 men, nearly a third of the whole party. Major Long, who had meanwhile reached Washington in a canoe, brought back orders for the discontinuation of the voyage up the Missouri, and for a journey overland to the sources of the Platte, whence the Mississippi was to be reached by way of the Arkansas and Red River. On the 6th June, the explorers left Engineer's Fort, as they called their winter quarters, and ascended the Platte Valley for more than a hundred miles, its grassy plains, frequented by vast herds of bisons and deer, supplying them with plenty of provisions.