Exploration of the Red River of Louisiana, in the year 1852 / by Randolph B. Marcy ; assisted by George B. McClellan. Page: 4 of 368

iv

INTRODUCTION.

Doctor George G. Shumard, of Fort Smith, Arkansas, who
faithfully discharged the duties of surgeon to the command,
also made important contributions to the department of natural
science, by collections of specimens of the rocks, minerals,
soils, fossils, shells, and plants, of the different localities which
we traversed; and of these, the plants were placed in the
hands of Dr. John Torrey, of New York, the eminent botanist
so well known to the army by his able reports on the collections
of Fremont, Emory, and others.
The shells were intrusted to Professor C. B. Adams, of
Amherst. His report, as presented, possesses a melancholy
interest, as being almost the last scientific effort of this distinguished
conchologist, whose loss science has so recently been
called upon to deplore.
The specimens of rocks and minerals have been examined
by President Hitchcock, of Amherst College, with important
results, while copious remarks on the general geology of the
country have been supplied by Dr. Shumard, who has also
furnished some notes on the conchology of the route.
The minerals and soils have been analyzed by Professor
C. U. Shepard, who detected among them a new species.
Finally, in the hands of Dr. Benjamin F. Shumard, the Tossils
have yielded several novelties to science. All these reports
upon the natural history of the expedition will be found detailed
at length in the appendix.
The barometrical observations which are given were taken
from both forms of the instruments, and exhibited a remarkable
agreement until the 8th of June, when we had the misfortune
to break the mountain barometer, and were obliged
subsequently to depend solely upon the aneroid. This I believe
to be very reliable, as it has been tested since our return
by a careful comparison with several other instruments in
possession of Benjamin Pike
and during such periods the command devolved upon