it available for many purposes to which the steam-engine would never
be applied.

In addition to his regular professional avocations, Ericsson was
industriously occupied in devising new applications of the
Calorie-Engine, when the attempted secession of the Southern States
plunged the country into the existing war and struck a blow at all the
arts of peace. Ills whole heart and mind were given at once to the
support of the Union. Liberal in all his ideas, he is warmly attached
to republican institutions, and has a hearty abhorrence of intolerance
and oppression in all their forms. His early military education and
his long study of the appliances of naval warfare increased the
interest with which he watched the progress of events. The abandonment
of the Norfolk navy-yard to the Rebels struck him as a disgrace that
might have been avoided. He foresaw the danger of a formidable
antagonist from that quarter in the steamship which we had so
obligingly furnished them. The building of gun-boats with
steam-machinery _above_ the water-line--where the first shot from
an enemy might render it useless--seemed to him, in view of what he
had done and was ready to do again, a very unnecessary error. Knowing
thoroughly all the improvements made and making in the war-steamers of
England and France, and feeling the liability of their interference in
our affairs, he could not appreciate the wisdom of building new
vessels according to old ideas. The blockade of the Potomac by Rebel
batteries, in the very face of our navy, seemed to him an indignity
which need not be endured, if the inventive genius of the North could
have fair play.

An impregnable iron gun-boat was, in his judgment, the thing that was
needed; and he determined that the plan of such a vessel should be his