w the water-line to three-fourths of an inch above
it. And if we allow for the superior strength and toughness of American
iron, an additional plate of three inches in thickness would suffice
to give them more strength than that of either the French or English
mail-clad steamers.

By careful computation we have ascertained that each vessel might be
encircled by such plates, weighing but one hundred and twenty pounds per
superficial foot, and have her bulwarks plated also, without adding more
than three hundred tons to her weight,--actually less than one-third of
the cargo she was designed to carry. With an extra planking within, and
an armament of twenty-four rifled fifty-pounders or Whitworth cannon,
and select crews, such vessels need fear no antagonists upon the deep.
Low in the hull, they would offer but little surface to the fire of the
enemy, and their sides would be impervious to shot and shell. Beneath
the decks they could carry in safety a whole regiment of troops.
Selecting their position by superior speed, they could destroy a fleet
of wooden steamers or ships-of-the-line. Entering any of our large
seaports, they could pass the fortress at the entrance uninjured, and
lay cities under contribution, or destroy their ports, without being,
like Achilles, or the English "Warrior," vulnerable in the heel.

When such steamers come into general use, we shall hear no more of the
wooden walls of Greece or England, or of those modern platforms which
had not a stick of sound oak timber in them,--nothing, indeed, but
pitch-pine and cypress. Oak, pine, and cypress would fall into the same
category, when contrasted with the imperishable iron. Some new agency of
steel must be invented to cope with the adamantine iron. And it becomes
our Government, both for the armament of our ships and for defence
against iron steamers, to adopt at the earliest moment every improvement
in rifled cannon.

The Navy Department has recently put under contract seven steamships and
several steam gun-boats. They have intrusted the latter to some of the
ablest ship-builders of the country, and it is well understood that most
of these vessels are to be completed the present season. This measure,
as far as it goes, is eminently wise; but our navy must still be below
the requirements of the nation, and entirely disproportioned to the
extent both of our commerce and of our sea-coast. At a low estimate, our
country requires an additional supply of at