Читать книгу Triumphs and Wonders of the 19th Century: The True Mirror of a Phenomenal Era - James P. Boyd - Страница 23
IV. THE PROGRESS OF NAVAL ENGINEERING.
Оглавление“I have just read the project of Citizen Fulton, Engineer, which you have sent me much too late, since it is one which may change the face of the world.”
So, in the beginning of the century, wrote the first Napoleon from his Imperial camp at Boulogne. Wrapped in his day-dream of a descent upon the Thames, he saw, with prophetic vision, in the plans of the American engineer, the future of navigation, and he strove to grasp—but too late—the opportunity which might have made his armada victorious over wind and tide.
His words, however, rang truer than he knew. On the sea, as on the land, the engineer has indeed “changed the face of the world;” and in no department of human progress has his influence been more radical or more far-reaching than in the mechanism, the scope, and the strategy of naval war. Fleets move now with a swiftness and surety unthought of in the days of sail. Over the same western ocean which Nelson, in his eager chase of Villeneuve, crossed at but four knots an hour, the United States cruiser Columbia swept, ninety years later, at a speed nearly four and three quarters times that of his lagging craft. When, in 1898, war came, the great battleship Oregon, although far to the northward on our western coast, was needed in the distant battle-line off the Cuban shore. In 79 days she steamed 14,500 miles, making a run which is without parallel or approach by any warship of any navy in the world’s history. The magnificent manhood, the unconquerable pluck, the engineering skill, which brought her just in time off Santiago, won their reward when the Colon struck her flag. Speed has been a determining factor in many a naval action. It was that which gave the power to take and hold the old-time “weather-gauge.” None knew its value better than Nelson, the chief fighter of the age of sail. Once he said that there would be found, stamped upon his heart, “the want of frigates,” the swift and nimble “eyes of the fleet” in his day. If his career in warfare on the sea had been a century later, he would be found foremost among the advocates of high-speed battleships and quick-firing guns.
It is, however, not only in the speed of warships that steam and mechanism have revolutionized fleets. For example, the displacement of the battleship of to-day is fully three and one half times greater than that of her heaviest ancestor of the sailing age. With due limitation as to length of hull, it is evident that the wind would be, at best, a wholly inadequate and untrustworthy motor for this huge structure with its great weight of armor. It is true that, during the era of transition, sail and steam were both applied to iron-clads—this absurdity reaching its climax in the British Agincourt and her sisters, which were 400 feet long, 10,600 tons’ displacement, and were fitted with five masts. It is said that a merchant steamer narrowly escaped collision at night with one of these vessels, believing from her length and rigging that there were two ships ahead, between which she could pass. What these large displacements mean, in contrast with those of past days, will be, perhaps, best illustrated by the statement that the Italia of 13,600 tons—a ship with which, in her day, Italy challenged the criticism of the world—carries on her deck a weight, in armor and armament, of 2500 tons, or one fourth more than that of Nelson’s flagship Victory.
PLATE II. SIDE VIEW OF CONSTITUTION FROM ORIGINAL DRAWING.
(Furnished by the Author.)
Length | 174 ft. 10½ ins. |
Beam | 43 ft. 6 in. |
Mean Draught | 20 ft. 0 in. |
Displacement | 2200 tons. |
William Doughty, Fecit. 1796, Oct.
Joshua Humphreys, of Philadelphia, Designer. Cloghorne and Hartley, of Boston, Builders. Launched Oct. 21, 1797.
Again, the largest naval gun in the year 1800 was one firing but a 42-pound shot, while in the United States navy we have now the 13-inch rifle of 60 tons, with a projectile of 1100 pounds, and Great Britain has afloat 1800-pounder breech-loaders which weigh 111 tons. Before monster ordnance such as this, the strength of man, unaided, is but crude and futile. He must call to his help—as he has done—steam as the source of power for the electric, hydraulic, or pneumatic engines, which load, elevate, and train the gun.
In summing up the service of steam, directly or indirectly, to the ship-of-war, it will be seen that the speed of the battleship has been increased by fully 50 per cent., and that of the cruiser has been doubled; that the displacement of the battleship is now three and one half times that of her sailing predecessor; and that, since the century’s birth, the gun has grown to such extent that the projectile for the Oregon’s main battery weighs 26 times that of the heaviest shot in the year 1800. This, however, is not all. Steam acts primarily, as well, to raise the anchor, to steer the ship, and to effect her lighting, heating, drainage, and ventilation. To the genius of James Watt there must be ascribed the possibility for the growth and change which have produced the modern man-of-war.
Closely allied with mechanism in this evolution, has been the transformation of the structural material of the hull, which has passed from the hands of the shipwright in wood to the engineer who works with steel. The reasons for this are not far to seek. They lie, firstly, in the greater strength of the metal construction to withstand the vibration of swift and heavy machinery, and the strains arising from the unequal distribution of massive weights in a hull which pitches or rolls with the waves. With wooden ships, the present proportions would have been unattainable. Again, there is a marked saving in the weight of the hull proper of the steel vessel, which is not only stronger but lighter. This weight in the days of timber averaged fully one half of the displacement; while in the Oregon, whose tonnage, at normal draught, is 10,288, the hull percentage is 44.06, leaving a gain over the wooden vessel of 611 tons to be applied to armor, armament, or equipment. Finally, the durability of the metal vessel, with adequate care, greatly exceeds that of the wooden war steamer, whose average life was but 13 years.
The creation of the steam machinery of navies has been the achievement of the engineers of practically but three great nations. The daring of France, the inventive genius of America, and the wide experience and sound judgment of Great Britain, have united in this work. Our country has led time and again in the march of improvement; although our progress has been fitful, since, more than a generation ago, we turned from the sea to the development of the internal resources of this continent. Limits of space permit but brief review of a history which has had its full share of triumphs, not only in battle, but over wave and wind.
THE U.S.S. OREGON.
A contemporary authority states that, when British Admiral Sir John Borlase Warren ascended the Potomac River, during the war of 1812, his expedition was reconnoitred by an American steamer. This appears to be the first record of the use of such craft for military purposes. In 1814 the United States built the first steam war-vessel in the world’s history. She was called the Demologos, later the Fulton, and her completion marked truly, as her commissioners said, “an era in warfare and the arts.” She was a double-ended, twin-hulled floating battery of 2475 tons, carrying twenty 32-pdr. guns, protected by 4 ft. 10 in. of solid timber. She was driven by a single central paddle-wheel; her speed was 5½ miles per hour; and she was both handy and seaworthy. France, in 1820, sent a commission to America to report upon steam vessels of war; and in 1830 the French had nine armed steamers afloat and nine building. In 1821, the Comet, a small side-wheeler, was commissioned as the first steam war-ship in the British navy, and in 1840, at the bombardment of Acre, steam vessels fought their first battle.
ACTION BETWEEN MONITOR AND MERRIMAC.
The growth of steam in navies had been retarded by its application solely to paddle craft, whose wheels and machinery were incapable of protection in action. During the years 1842–43, however, the United States built the sloop-of-war Princeton, of 954 tons. This vessel was the product of the genius of John Ericsson, the ablest marine engineer the world has ever seen. She was the first screw-propelled steam warship ever built, and, in other respects, foreshadowed the advances which were to come. Thus, her machinery was the first to be placed wholly below the water-line beyond the reach of hostile shot; her engine was the first to be coupled directly to the screw shaft, and blowers, for forced draft, were with her first used in naval practice. She was virtually the herald of the modern era.
The Princeton was followed closely by the Rattler, the first screw vessel of the British fleet, and in 1843–44 the French 44-gun frigate Pomone was fitted with propellers. In 1843, also, the English Penelope was the first man-of-war to be equipped with tubular boilers, and the year 1845 was notable for the building of the ill-fated Birkenhead, the first iron vessel of the British fleet. In 1850, when the French constructed the screw line-of-battle ship Napoleon, the English became alarmed, and began with vigor the renovation of their navy with regard to screw propulsion.
France, in 1854, laid the keels of four armored batteries, three of which, forming the first ironclad squadron in history, went into action a year later under the forts of Kinburn in the Crimea. They were of 1600 tons’ displacement, carried 4⅓ inch armor and sixteen 68-pdr. guns, and had a speed of four knots. In 1862, Ericsson launched the famous Monitor, the first sea-going ironclad with a revolving turret, and an “engineers’ ship” from keel to turret top.
THE TURBINIA.
The Civil War found us with a sailing navy, and left us one of steam. Passing over its victories, in which steamers played always the chief part on sea and river, we come to that most notable triumph of Chief Engineer Isherwood, the cruiser Wampanoag of 4200 tons’ displacement. This vessel, phenomenal in her day, steamed in February, 1868, from Barnegat to Savannah, over a stormy sea, in 38 hours. Her average was 16.6 knots for the run, and 17 knots during a period of six consecutive hours—a speed which for 11 years thereafter was unapproached by liner or by warship. In 1879, the British despatch vessel Mercury, of 3730 tons and 18.87 knots, wrested the palm from America; but, in 1893, it was won again for the United States by the triple-screw fliers Columbia and Minneapolis of 7475 tons, with speeds respectively of 22.8 and 23.073 knots. The laurels rest now with the Buenos Ayres, which, though built in England in 1895, flies the flag of Argentina. She has a tonnage of 4500 and a speed of 23.202 knots.
ENGINE OF U.S.S.POWHATAN. A.D. 1849.
PLATE III.
The British ironclad Pallas, completed in 1866, was remarkable for having the first successful naval engines on the compound principle, in which the steam is admitted at high pressure to a small cylinder, and passes thence to a larger one which it fills by its expansion. To Great Britain the world owes also the development of triple expansion, i.e., the use of steam successively in three cylinders. This system was inaugurated in naval engines by the British, in 1885–86, and is now universally employed. Prior to 1879, the boilers of all modern war-vessels had been those of the Scotch type, in which the flame passes through tubes fixed in a cylindrical shell containing water. In that year, however, France began a revolution in the steam generators of navies by equipping a dispatch-vessel with the Belleville tubulous boiler, in which the water to be evaporated is contained within tubes surrounded by flame confined in an outer casing. The water-tube principle, also, bids fair to become of universal application. It has had its most noteworthy naval installation in the British cruisers Powerful and Terrible, of 14,200 tons and 25,886 horse-power, completed in 1895.
PLATE IV. ENGINE OF U.S.S. ERICSSON.
The use of more than one screw for propulsion dates back to 1853. During our Civil War multiple screws figured, to a small extent, in the “tin clads” and larger monitors. The application of twin screws, in the modern era, begins with the British ironclad Penelope of 1868. France, in the years 1884–85, blazed the way for another naval advance of much importance in conducting a series of trials with the launch Carpe, equipped with triple screws. The system, however, although of much value, from engineering and tactical points of view, was not adopted in large, high-powered vessels until the advent of the French armored cruiser Dupuy de Lôme in 1890, and the protected cruisers Columbia and Minneapolis of the United States navy in 1893. It has now won full approval in the navies of continental Europe, and triple-screw ships, aggregating 500,000 tons, are built or building there.
The limits of space forbid more than a passing note of the triumphs of the engineer in torpedo craft, the light cavalry of the sea. With steamers of normal proportions, the speed and power depend largely upon, and increase with, the displacement. As has been stated, the maximum performance of large cruisers is now 23 knots on a tonnage of 4500. These particulars give a faint glimpse of the extraordinary problem which has confronted the torpedo-boat designer in driving hulls of, at present, about 150 tons at a speed which now approximates to 30 knots. With the brilliant record of success in this task, there will be linked always the names of Yarrow and Thornycroft in England, of Schichau in Germany, and of Normand in France. The achievement but recently of a British inventor, the Hon. Charles Algernon Parsons, in giving the Turbinia of 44.5 tons a speed of over 31 knots, has drawn the attention of engineers the world over to the possibilities of the steam turbine on the sea. This performance is phenomenal with such a displacement. The French Forban, of 130 tons, has made 31.2 knots, and a reported speed of 35 knots gives a Schichau boat her temporary laurels as the fastest craft afloat.
A brief glance at the improvements which have made possible these extreme speeds in cruisers and torpedo craft will be of interest. The progress which has been made has been, firstly, in the economy in the use of steam arising from higher pressures and multiple expansion; secondly, in the reduction of weight, per horse power, due to increase in strength of materials and in engine-speed with the employment of forced draft—which was reintroduced by France—and the water-tube boiler; and, finally, in the application of a more efficient propelling instrument. The advances of half a century in propelling machinery are shown, in some respects, by Plates III and IV, which contrast, on the same scale, the side-wheel machinery of the United States war-steamer Powhatan, of 1849, with the engines of the United States torpedo boat Ericsson of to-day. The data of the former vessel are: horse-power, 1172; steam pressure 15 lbs.; weight of machinery per horse-power 972 lbs.; while, for the Ericsson, the figures are: horse-power, 1800; steam pressure, 250 lbs.; weight of machinery per horse-power, 56 lbs. This comparison, however, must be qualified by the statement that the older engine was for a steamer of about 3760 tons, while the torpedo boat is but 120 tons in displacement. The contrast lies, therefore, only in the reduced weight of material per horse-power developed and in the increased steam pressure, which, however, are in themselves most striking.