FT. IN.
Length extreme. 262 6.40
Length at load-line. 234 0.94
Beam. 53 8.38
Height between decks. 6 8.72
Height of lower port sill. 7 2.63
Depth of hold. 26 9.34
Deep-load draft. 25 3
Immersed cross section, sq. ft. 1063.48
Displacement. tons. 6050
Diameter of cylinders. 8 2.45
Length of stroke. 5 3.06
Diameter of propeller. (4 bladed) 19 0.70
Pitch " " mean) 37 11
She has eight boilers, each having five furnaces, consuming, at full speed, (12.14 knots,) 143 tons of coal per day, for which she stows five days' supply. The boilers and engines occupy eighty-two feet in the length of the ship.
The trial of this ship has established the practicability of adapting a propeller to a ship of the largest class, so as to insure great speed, and constitute a most effective man-of-war for certain purposes and in certain situations; but when the great weight of the engines is considered, and the large space they occupy in the vessel,—thereby diminishing the stowage of supplies,—and further, that, after the coal is exhausted, the ninety-gun ship has but the sail of a sixty-gun ship to rely upon, it is not easy to avoid the conclusion, that, however useful such a vessel may be for short passages,[1] and in those seas in which her supplies of coal and provisions may be constantly replenished, her sphere of action must be very limited, and she could not be relied upon for the long cruises and various services on which an ordinary line-of-battle ship is employed.
[Footnote 1: For debarking a regiment or two of Zouaves on the shores of the Adriatic or upon the coast of Ireland.]
A ship constructed on the plan of the Napoléon, for the sake of gaining a speed of twelve knots per hour for the distance of about two thousand two hundred miles, is compelled to sacrifice a great part of her efficiency in several most important particulars.
In time of war, at short distances from port, for the defence of bays or harbors or the Florida channel, for the speedy transport of troops to an adjacent coast, or to force a blockade, such a vessel would undoubtedly be a most valuable addition to our navy: but her employment must necessarily be confined to such circumstances and such situations; for should she unluckily fall in with an enemy's squadron, with her coal expended, or her machinery rendered useless by any of the numerous accidents to which steam-machinery is so constantly exposed, with her comparatively light rig, and want of stability in consequence of losing so great a weight of coals, she would hardly prove a very formidable opponent.
Therefore, while admitting the importance and necessity of providing for special service a small class of fast, full-power steamers, it is submitted that the auxiliary screw-steamer is the description of ship to which the largest and best consideration should be devoted; for to the nation possessing the most efficient fleet of such vessels must belong the dominion of the sea. And while their cost is counted, let it at the same time be remembered that their value can be estimated only by the character of the service they may render, and that their capacity for aggression abroad makes them the best defence at home.
Having briefly referred to the various views entertained in regard to the steam-power with which the navy should be furnished, it will be seen that a difference of opinion on this important subject may most reasonably be entertained.
None can doubt the advantages of celerity to a man-of-war, yet many believe it would be too dearly purchased by the sacrifice of space to such an extent as would require supplies to be often replenished; as this necessity would in war confine the operations of the navy to our own shores.
On the other hand, it is admitted, that, without high speed, a ship of war cannot exercise many of her most important functions,—that she can neither choose an engagement, protect a convoy, nor enforce a blockade.