THE UNITED STATES STEAMSHIP COLUMBIA.
An appropriate addition to the White Squadron of the United States navy was launched from the Cramps' ship-yard at Philadelphia, July 26, 1892, and was most appropriately christened the Columbia. The launch was in every way a success, and was witnessed by many thousand people, including Secretary Tracy, Vice-President Morton, and others prominent in the navy and in public life.
This new vessel is designed to be swifter than any other large war vessel now afloat, and she will have a capacity possessed by no other war vessel yet built, in that of being able to steam at a ten-knot speed 26,240 miles, or for 109 days, without recoaling. She also possesses many novel features, the principal of which is the application of triple screws. She is one of two of the most important ships designed for the United States navy, her sister ship, No. 13, now being built at the same yards.
The dimensions of the Columbia are: Length on mean load line, 412 feet; beam, 58 feet. Her normal draught will be 23 feet; displacement, 7,550 tons; maximum speed, 22 knots an hour; and she will have the enormous indicated horse-power of 20,000. As to speed, the contractor guarantees an average speed, in the open sea, under conditions prescribed by the Navy Department, of twenty-one knots an hour, maintained for four consecutive hours, during which period the air-pressure in the fire-room must be kept within a prescribed limit. For every quarter of a knot developed above the required guaranteed speed the contractor is to receive a premium of $50,000 over and above the contract price; and for each quarter of a knot that the vessel may fail of reaching the guaranteed speed there is to be deducted from the contract price the sum of $25,000. There seems to be no doubt among the naval experts that she will meet the conditions as to speed, and this is a great desideratum, since her chief function is to be to sweep the seas of an enemy's commerce. To do her work she must be able to overhaul, in an ocean race, the swiftest transatlantic passenger steamships afloat.
The triple-screw system is a most decided novelty. One of these screws will be placed amidships, or on the line of the keel, as in ordinary single-screw vessels, and the two others will be placed about fifteen feet farther forward and above, one on each side, as is usual in twin-screw vessels. The twin screws will diverge as they leave the hull, giving additional room for the uninterrupted motion upon solid water of all three simultaneously. There is one set of triple expansion engines for each screw independently, thus allowing numerous combinations of movements. For ordinary cruising the central screw alone will be used, giving a speed of about fourteen knots; with the two side-screws alone, a speed of seventeen knots can be maintained, and with all three screws at work, at full power, a high speed of from twenty to twenty-two knots can be got out of the vessel. This arrangement will allow the machinery to be worked at its most economical number of revolutions at all rates of the vessel's speed, and each engine can be used independently of the others in propelling the vessel. The full steam pressure will be 160 pounds. The shafting is made of forged steel, 16½ inches in diameter. In fact, steel has been used wherever possible, so as to secure the lightest, in weight, of machinery. There are ten boilers, six of which are double-ended—that is, with furnaces in each end—21¼ feet long and 15½ feet in diameter. Two others are 18¼ feet long and 11⅔ feet in diameter, and the two others, single-ended, are 8 feet long and 10 feet in diameter. Eight of the largest boilers are set in watertight compartments.
In appearance the Columbia will closely resemble, when ready for sea, an ordinary merchantman, the sides being nearly free from projections or sponsons, which ordinarily appear on vessels of war. She will have two single masts, but neither of them will have a military top, such as is now provided upon ordinary war vessels. This plan of her merchantman appearance is to enable her to get within range of any vessel she may wish to encounter before her character or purpose is discovered. The vitals of the ship will be well protected with armor plating and the gun stations will be shielded against the firing of machine guns. Her machinery, boilers, magazines, etc., are protected by an armored deck four inches thick on the slope and 2½ inches thick on the flat. The space between this deck and the gun-deck is minutely subdivided with coal-bunkers and storerooms, and in addition to these a coffer-dam, five feet in width, is worked next to the ship's side for the whole length of the vessel. In the bunkers the space between the inner and outer skins of the vessel will be filled with woodite, thus forming a wall five feet thick against machine gun fire. This filling can also be utilized as fuel in an emergency. Forward and abaft of the coal bunkers the coffer-dam will be filled with some water-excluding substance similar to woodite. In the wake of the four-inch and the machine guns, the ship's side will be armored with four-inch and two-inch nickel steel plates.
The vessel will carry no big guns, for the reason that the uses for which she is intended will not require them. Not a gun will be in sight, and the battery will be abnormally light. There will be four six-inch breech-loading rifles, mounted in the open, and protected with heavy shields attached to the gun carriages; eight four-inch breech-loading rifles; twelve six-pounder, and four one-pounder rapid-firing guns; four machine or Gatling guns, and six torpedo-launching tubes. Besides these she has a ram bow. The Columbia is to be completed, ready for service, by May 19, 1893.