prevalence of the yellow fever in that city. He improved the time of his
quarantine at Staten Island by exploring its mineralogy and geology,
where he experienced a kind and appreciating reception from the health
officer, Dr. De Witt.

His reception also from scientific men at New York was most favorable,
and produced a strong sensation. Being the first person who had brought
a collection of its scientific resources from the Mississippi Valley,
its exhibition and diffusion in private cabinets gave an impulse to
these studies in the country.

Men of science and gentlemen of enlarged minds welcomed him. Drs.
Mitchell and Hosack, who were then at the summit of their influence, and
many other leading and professional characters extended a hand of
cordial encouragement and appreciation. Gov. De Witt Clinton was one of
his earliest and most constant friends. The Lyceum of Natural History
and the New York Historical Society admitted him to membership.

Late in the autumn of 1819, he published his work on the mines and
mineral resources of Missouri, and with this publication as an exponent
of his views, he proceeded to Washington, where he was favorably
received by President Monroe, and by Mr. Calhoun and Mr. Crawford,
members of his cabinet. At the request of the latter he drew up a memoir
on the reorganization of the western mines, which was well received.
Some legislation appeared necessary. Meantime Mr. Calhoun, who was
struck by the earnestness of his views and scientific enterprise,
offered him the situation of geologist and mineralogist to an exploring
expedition, which the war department was about dispatching from Detroit
to the sources of the Mississippi under the orders of Gen. Cass.