To make the exploration as useful as possible, I determined, in conformity
to your general instructions, to vary the route to the Rocky mountains
from that followed in 1842. The route was then up the valley of the Great
Platte river to the South Pass, in north latitude 42 deg.; the route now
determined on was up the valley of the Kansas river, and to the head of
the Arkansas river, and to some pass in the mountains, if any could be
found, at the sources of that river.

By making this deviation from the former route, the problem of a new road
to Oregon and California, in a climate more genial, might be solved; and a
better knowledge obtained of an important river, and the country it
drained, while the great object of the expedition would find its point of
commencement at the termination of the former, which was at that great
gate in the ridge of the Rocky mountains called the South Pass, and on the
lofty peak of the mountain which overlooks it, deemed the highest peak in
the ridge, and from the opposite side of which four great rivers take
their rise, and flow to the Pacific or the Mississippi.

Various obstacles delayed our departure until the morning of the 29th,
when we commenced our long voyage; and at the close of a day, rendered
disagreeably cold by incessant rain, encamped about four miles beyond the
frontier, on the verge of the great prairies.

Resuming our journey on the 31st, after the delay of a day to complete our
equipment and furnish ourselves with some of the comforts of civilized
life, we encamped in the evening at Elm Grove, in company with several
emigrant wagons, constituting a party which was proceeding to Upper
California, under the direction of Mr. J.B. Childs, of Missouri. The
wagons were variously freighted with goods, furniture, and farming
utensils, containing among other things an entire set of machinery for a