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water, where he will find extensive offices, and two large buildings which cover the vessels upon the stocks.
As he approaches these structures, he will notice many plates of superior iron from the rolling-mills of Baltimore, combining the toughness and strength and other excellences of the best Pennsylvania iron; he will notice, too, immense ribs and beams of iron, and hear the incessant din of hammers riveting the sides and boilers.
Under each of these sheds he will find an iron steamship, two hundred and seventy-five feet in length by twenty-three in depth, exquisitely proportioned; he will be struck by the fine entrance and run. The extreme sharpness of the stem and stern, combined with great capacity, seems to answer every requirement; and he will be surprised to learn that the draught of these steamers is but sixteen feet when deeply laden, and that their engines of thirteen hundred horse-power are expected to give them a speed of fifteen knots per hour. When they reach their destined element and have received their lading, the height from the water-line to the deck will be but seven feet; hence it is apparent that a belt of iron plates carried around them of eight feet four inches in height would protect them from the deck to a point sixteen inches below the water-line, or from the bottom of the deck-beams to a point two feet below the water-line.
The iron plates which form the sides of these ships range in thickness from one inch below 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