life.

In connection with his naval designs, he devoted much study to the
improvement of heavy ordnance, both as to the gun and its mounting. In
particular, his mounting of the guns in the "Monitor" was quite
original, and the friction arrangement for absorbing the recoil was a
great improvement over methods then in use, and served as a model for
many copies and adaptations of the same principles in later years by
other designers. In 1863 he also designed and built for the acceptance
of the Government a forged 13-inch wrought-iron gun. While his design
was an advance on those of the day, the demands on the makers of iron
forgings were more than could be successfully met, and the gun developed
some slight cracks in the test, which prevented further developments on
this line. Ericsson always maintained that the tests to which this gun
was submitted were unfairly severe, and he showed how the defects could
be remedied by a steel lining. But the Naval Bureau of Ordnance insisted
that this should be done at his own expense, and as he had already lost
some $20,000 on the gun, he was unwilling to proceed farther, and the
matter was allowed to lapse.

Throughout his entire career the improvement of the steam-engine
occupied a large share of Ericsson's attention, and in particular was
this the case in connection with his naval designs. From the
"Princeton," in 1841, to the "Destroyer," in 1878, there succeeded one
long series of types and forms of steam-engine, each in his opinion the
best adapted to the circumstances of the case. Naturally, opinions
differ, and he was brought into competition with other able engineers,
and his designs were often called into question or subjected to
criticism. In 1863, in competition with Chief Engineer Isherwood of the
navy, engines were designed for twin ships, the "Madawaska," afterward
known as the "Tennessee," and the "Wampanoag," afterward called the
"Florida." This was a battle royal of types and modes of application of
the power of the steam-engine to the propulsion of ships. The result was
a victory for Isherwood, although the "Madawaska," which was first
subjected to trial, made a speed higher than any warship at that time
afloat. This was exceeded by the "Wampanoag" a short time later; but
neither engine was of an enduring type, and after a time the machinery
of the "Madawaska" was removed, and she was repowered with a later type
of machinery, and long did service as the "Tennessee"