The period 1850-60 cannot be passed over without a mention of the Great Eastern, though she can hardly be said to have been in the line of practical development, which was not so much in enlargement of hull as in change in character of machinery. Brunel’s son, in his “Life” of his father, says: “It was no doubt his connection with the Australian Mail Company (1851-53) that led Mr. Brunel to work out into practical shape the idea of a great ship for the Indian or Australian service, which had long occupied his mind.”
The Great Eastern was to attempt to solve by her bulk the problem of coal capacity which was later to be solved by high pressures and surface condensation. The ship finally determined on was 680 feet long, 83 feet broad, with a mean draught of 25 feet, with screw engines of 4,000 indicated horse-power and paddle-engines of 2,600, to work with steam from 15 to 25 pounds pressure—thus curiously uniting in herself at this transition period the two rival systems of propulsion. She was begun at Millwall, London, in the spring of 1854, and was finally launched, after many difficulties, on January 30, 1858. Her history is too well known to be dwelt upon here. She has experienced many vicissitudes and misfortunes, and it is well that her great projector (who paid for her with his life, as he died the year after her launching) did not live to see her used as an exhibit, in 1886, in the River Mersey, her great sides serving to blazon the name and fame of a Liverpool clothing establishment. She was sold the next year for the pitiful sum of £8,000 and broken up.
The year 1855 marks the high-water mark of the paddle-steamer era. In that year were built the Adriatic, by the Collins line, and the Persia, as a competitor (and the twenty-eighth ship of the company), by the Cunard. But the former was of wood, the latter of iron. She was among the earlier ships of this material to be built by the Cunard company, and, with the slightly larger Scotia, built in 1862, was, for some years after the cessation of the Collins line, the favorite and most successful steamer upon the Atlantic. She was 376 feet long, 45 feet 3 inches broad, and of about 5,500 tons displacement. Her cylinders were 1001⁄2 inches diameter, with 120 inches stroke, and she had—as also the preceding ship, the Arabia—tubular boilers instead of the old flue.
Model of the Persia and Scotia.
Diagram showing Decrease in Expediture of Coal per indicated Horse-power per hour based on Good Average Practice
Diagram showing increase in Steam-pressures based on good average Practice