f July, and that the
same day was made triply memorable by the capture of Vicksburg with
Pemberton's entire army of 30,000 men with all their guns and
ammunitions. These two striking events threw the country into the
wildest enthusiasm. Even the most despondent now became confident that
the Southern Confederacy would soon be destroyed, and that the
triumphant Union would be finally re-established. But this confidence
was destined to be rudely shaken.

Later in the summer, taking advantage of the lull in operations
elsewhere, the Confederate leaders sent Longstreet's splendid corps of
veterans from Virginia, and that part of Johnston's army which had been
paroled, together with such detachments as could be got from Alabama,
to reinforce Bragg, who had been driven by Rosecrans from Middle
Tennessee to Northern Georgia. Turning fiercely upon his over-confident
pursuer, as soon as his reinforcements were at hand, Bragg struck a
staggering blow at Chickamauga, which not only came near giving
Chattanooga back to him, but filled the northern states with
consternation. The war was not only not ended, but had burst forth with
renewed vigor. Reinforcements in large numbers were hurried forward
from all parts of the country to Chattanooga. Hooker, with Howard's and
Slocum's corps, was sent out by rail from Virginia, while the greater
part of Grant's Army of the Tennessee was withdrawn from the lower
Mississippi, where it was resting after the capture of Vicksburg, and
marched over-land from Memphis to the same place. The separate
departments in the Mississippi Valley were consolidated into a military
grand division, under the supreme command of General Grant, and what
turned out to be of almost equal importance was the fact that Brigadier
General William F. Smith was relieved from service in West Virginia,
where he had been recently assigned to duty, and sent to contribute his
part towards strengthening the national grasp upon the vast region of
which Chattanooga was justly considered the strategic center.

Whatever the government at that time may have thought of him as a
commander of troops, it is certain that it was willing to recognize and
use his experience and marked intellectual resources as an engineer
officer to their fullest extent. As it turned out, it could not have
paid him a greater compliment, nor given him a better opportunity for
distinction. His fame had gone before him, and on his arrival at
Chattanooga, althou