med back to her landing. As the telegraph that night
flashed over the land the news of the Merrimac's victory, dismay filled
the North, exultation the South. What was to stay the career of the
invulnerable monster? Could it not destroy the whole United States navy
of wooden ships?

Next morning the Merrimac reappeared to complete her work of
destruction. As she drew near the stranded Minnesota, a strange little
craft moved out from the side of the big frigate and headed straight for
the iron-clad. It was Ericsson's Monitor, which had arrived from New
York at midnight. The Confederate characterization of it as a "cheese-box
on a raft" is still the best description of its appearance. Its
lower hull, 122 feet long and 34 wide, was protected by a raft-like
overhanging upper hull, 172 feet long and 41 wide. Midway upon her low
deck, which rose only a foot above the water, stood a revolving turret
21 feet in diameter and nine in height. It was made of iron eight inches
thick, and bore two eleven-inch guns throwing each a 180-pound ball.
Near the bow rose the pilot-house, made of iron logs nine inches by
twelve in thickness. The side armor of the hull was five inches thick,
and the deck was covered with heavy iron plates.

[Illustration: Portrait.]
John Ericsson.

[Illustration: Cross section of monitor.]
Sectional View of Monitor through Turret and Pilot House.

[1863]

For three hours the iron-clads fought. The Merrimac's shot glanced
harmlessly off the round turret, while her attempts to run the Monitor
down failed. Meanwhile the big guns in the Monitor's turret, firing
every seven minutes, were pounding the ram's sides with terrible blows.
The Merrimac's armor was at points crushed in several inches, but
nowhere pierced, About noon the fight stopped, as if by mutual consent.
It was a drawn battle, but the career of the Merrimac had ended. Upon
McClellan's advance, in May, she was blown up. The Monitor received no
serious injury in this action, but the next December she foundered in a
storm off Cape Hatteras.

The invention of the Monitor revolutionized naval warfare, and set
European nations to building the ponderous iron-clad navies of the
present day. The United States Government soon contracted for twenty
single-turret monitors, and four double-turreted ones with fifteen-inch
guns.

The Confederates now went to building iron-clads on the model of the
Merrimac. On the morning of January 31, 1863, the iron-c