r times would quicken every
pulse, and arrest universal attention, pass all but unnoticed; as
historians record that during the battle between Hannibal and the Romans
by the Lake Thrasymene, the earth was shaken and upheaved by a great
natural convulsion, without attracting the observation of the fierce,
eager combatants; or, as Byron tersely phrases it,

'An earthquake rolled unheededly away,'

being regarded, if regarded at all, as one of the incidents of the
tremendous collision of Europe with Africa.

When, early in March, 1844, John C. Fremont, with thirty or forty
followers, astonished Captain Sutter by dropping down from the Sierra
Nevada upon his _ranche_ on the Sacramento, the old Switzer could not
have been more completely dumbfounded had he been told that his visitors
had just descended from the clouds, than he was by the truthful
assurance that they were an exploring party, who had left the United
States only ten months before, and had since made their way across the
continent. To pass the Sierra in winter had hitherto been deemed an
impossibility, and, indeed, the condition of Fremont's surviving beasts
of burden--thirty-three out of the sixty-seven with which he
started--proved the presumption not far out of the way. To traverse the
continent at all, even in summer, on a line stretching due west from the
Hudson, the Delaware, or the Potomac, to the Pacific Ocean, was an
unattempted feat, whereof the hardships, the dangers, were certain, and
the success exceedingly doubtful. A very few parties of daring
adventurers had, during several of the six or eight preceding summers,
pushed up the Platte from the Missouri to the Rocky Mountains, followed
the Sweetwater from the point where the North Platte emerges from the
heart of those mountains, running to the northward, and having thus
passed through the great central chain of North America (for the
Sweetwater heads on the west side of the mountain range, and the South
Pass, through which it seeks the Platte, is a broad elevated gap,
wherein the face of the country is but moderately rolling, and the trail
better than almost any where else), turned abruptly to the north-west,
crossed the Green River source of the Colorado, which leads a hundred
miles farther north, and soon struck across a mountainous water-shed to
the Lewis or Snake branch of the Columbia, which they followed down to
the great river of the west, and thus reached the coveted shore of the
Pacif