no reward or profit, for he
was only anxious to help France in her warfare with Russia, the hereditary
foe of Sweden. The war was drawing to a close, and for his future projects
the Emperor wanted large sea-going ships, not light-draught vessels for
work in the shallows of the Baltic. So Ericsson received a complimentary
letter of thanks and a medal, and kept his design for later use. His
opportunity came in the first months of the Civil War.

In the fifty years between the war of 1812 and the outbreak of the
struggle between North and South, the American navy had been greatly
neglected. It was a favourite theory in the United States that a navy
could be improvised, and that the great thing would be, in case of war,
to send out swarms of privateers to prey upon the enemy's commerce. Very
little money was spent on the navy or the dockyards. On the navy list
there were a number of old ships, some of which had fought against
England in 1812. There were a number of small craft for revenue purposes,
a lot of sailing-ships, and a few fairly modern steam frigates and
smaller steam vessels depending largely on sail-power, and known as
"sloops-of-war"--really small frigates.

While the dockyards of Europe had long been busy with the construction of
the new armoured navies, the United States had not a single ironclad. Both
parties to the quarrel had to improvise up-to-date ships.

Sea power was destined to play a great part in the conflict. As soon as the
Washington Government realized that it was going to be a serious and
prolonged war, not an affair of a few weeks, a general plan of operations
was devised, of which the essential feature was the isolation of the
Southern Confederacy. When the crisis came in 1861 the United States had
done little to open up and occupy the vast territories between the Rocky
Mountains and the Mississippi Valley. The population of the States was
chiefly to be found between the Mississippi and the Atlantic, and in that
region lay the states of the Confederacy. They were mainly agricultural
communities, with hardly any factories. For arms, munitions of war, and
supplies of many kinds they would have to depend on importation from beyond
their frontiers. It was therefore decided that while the United States
armies operated on the northern or land frontier of the Confederacy, its
sea frontiers on the Atlantic and the Gulf of Mexico should be closely
blockaded, and its river frontier, the line of the Mi