climate, and in 1817 returned to the seat of government
and submitted to the President a particular and elaborate memoir of
their operations. It was upon this first report, presented by the
Executive, on the Military Defences of the United States,--a report
drawn up in a very large degree by the hand of M. Poussin, and
illustrated throughout with his discovery and suggestion,--that
Congress, by an almost unanimous vote, authorized the erection of the
great line of our military defences, adopting the recommendations of the
commissioner without even the slightest alteration. The Board of
Military Engineers entered subsequently on the yearly execution of their
important duty of examining the coast previous to determining the actual
sites and descriptions of the works of defence which they afterwards
delineated. The young topographical engineer continued in his arduous
scientific labors, and thus contributed largely in the perfecting of
that great national scheme. It was in these military operations, and
afterwards in the surveys for roads and canals, which, under the
supervision of a Board of Internal Improvements, where confided to a
portion of the same officers, assisted by civil engineers, that Poussin
rendered himself so efficient as a practical and scientific surveyor,
and became so perfectly familiar with all the internal resources of our
extensive country, which he had thus most remarkable opportunities to
study and appreciate, by crossing it in all directions, and, in fact, by
visiting every state, and by following up and down every valley and
river of the eastern half of the continent. Few men have had such
occasion of studying _de visu_ the extent and resources of the republic;
and the intelligent readers of the volume before us will acknowledge,
that few persons have shown themselves more conversant with its
astonishing advancement. His first publication was a description of the
works to which he had contributed, under the title of "A History of the
Internal Improvements of the United States;" his second, an account of
all the railroads in this country, which had considerable influence in
developing in Europe a disposition toward our policy in this respect,
and entitles Major Poussin to the gratitude of all lovers of rapid and
safe communication. It was reproduced in Belgium and Germany, and has
long been a textbook upon its subject in those countries, as well as in
France. His third work was the one now translate