spread at the foot of the Rocky Mountains, and he planned an exploratory
expedition into that region. This bold and hazardous journey he
organized and commenced at Potosi early in the month of November, 1818,
and prosecuted it under many disadvantages during that fall and the
succeeding winter. Several expert and practiced woodsmen were to have
been of this party, but when the time for setting out came all but two
failed, under various excuses. One of these was finally obliged to turn
back from _Mine au Breton_ with a continued attack of fever and ague.
Ardent in the plan, and with a strong desire to extend the dominions of
science, he determined to push on with a single companion, and a single
pack-horse, which bore the necessary camp conveniences, and was led
alternately by each from day to day. A pocket compass guided their march
by day, and they often slept in vast caverns in limestone cliffs at
night. Gigantic springs of the purest crystaline water frequently gushed
up from the soil or rocks. This track laid across highlands, which
divide the confluent waters of the Missouri from those of the
Mississippi. Indians, wild beasts, starvation, thirst, were the dangers
of the way. This journey, which led into the vast and desolate parts of
Arkansas, was replete with incidents and adventures of the
highest interest.

While in Missouri, and after his return from this adventurous journey,
he drew up a description of the mines, geology, and mineralogy of the
country. Conceiving a plan for the better management of the lead mines
as a part of the public domain, he determined to visit Washington, to
submit it to the government. Packing up his collections of mineralogy
and geology, he ordered them to the nearest point of embarkation on the
Mississippi, and, getting on board a steamer at St. Genevieve, proceeded
to New Orleans. Thence he took shipping for New York, passing through
the Straits of Florida, and reached his destination during the