where I had the good fortune to receive his instruction in mathematics.
I first met him in the field, while I was serving temporarily on the
staff of General McClellan, and he was commanding a division in the
Antietam campaign, and next at Chattanooga, whither I was sent in
advance of General Grant to prepare for his coming, after the
disastrous battle of Chickamauga.

Shortly afterwards Smith was transferred to Grant's staff as Chief
Engineer, and we messed and served together, in the closest intimacy
throughout that campaign, and until I was assigned to duty in the War
Department in charge of the Cavalry Bureau. I saw him frequently while
I was commanding a division of cavalry and he an army corps in Grant's
overland campaign against Richmond. During the latter period we were
exceedingly intimate, and when we were not serving together an active
correspondence was kept up between us. It is a source of pleasure and
satisfaction to me that this intimacy became still closer after General
Smith was appointed agent of the United States and assigned as a civil
engineer to the charge of the river and harbor works on the Delaware
and Maryland peninsula, with his office at Wilmington, Delaware. This
long and close intimacy, extending as it did over the greater part of a
lifetime, has afforded me an ample opportunity of studying his
character and familiarizing myself with the facts of his military
career, and with the point of view from which he considered his
relations to the men and events with which he was so conspicuously
connected.

A man of great purity of character and great singleness of purpose, he
took an intense interest in whatever his hand found to do. He felt a
deep and abiding concern in all public and professional questions, and
was both a tender and affectionate friend and an unrelenting enemy. He