The ship was propelled by two separate engines, driving respectively paddle-wheels and a single propeller. The engines for the paddle-wheels were of the oscillating type. The cylinders were four in number, 74 inches in diameter, by 14-feet stroke, and each one in the finished condition weighed 28 tons. The paddle-wheels were 56 feet in diameter. Steam for these engines was supplied by four, double-ended, tubular boilers, each 17 feet 9 inches long, 17 feet 6 inches wide, and 13 feet 9 inches high, and weighing, with water, 95 tons. Each boiler contained 10 furnaces. The screw engines, which were placed in the aftermost compartment of the machinery spaces, were of the horizontal, opposed type; there were four cylinders, 84 inches in diameter, by 4-feet stroke, and each one, in the finished condition, weighed 39 tons. The propeller shafting, 150 feet in length, weighed 60 tons. The four-bladed propeller was 24 feet in diameter. Steam was supplied to these engines by six tubular boilers of about the same dimensions as those for the paddle-wheel engines. The working pressure was 25 pounds per square inch.
Length, 692 feet; beam, 83 feet; depth, 58 feet. Subdivision: Double hull; nine main bulkheads, 53 feet high, extending to upper deck, and six sub-bulkheads 35 feet high, extending to lower deck. Two longitudinal bulkheads through machinery spaces.
Longitudinal Section and Plan of the Great Eastern, 1858
The estimated speed of the Great Eastern was 15 knots; her best actual performance on an extended voyage was an average speed of 14 knots, which was realised on one of her trips to New York. She was designed to carry 4,000 passengers, namely 800 first, 2,000 second, and 1,200 third class, besides a crew of 400. She had a capacity of 5,000 tons of cargo, and 12,000 tons of coal. When fitted up for the accommodation of troops she could carry 10,000. Fully laden with passengers, cargo, and coal, she displaced, on a draft of 30 feet, about 27,000 tons;—her actual draft was from 26 to 28 feet. The accommodations for passengers would have done credit to one of our modern liners. There were five saloons on the upper, and another five on the lower deck. The uppermost deck afforded two unbroken and spacious promenades, one on each side of the ship, each of which was 20 feet wide and over 600 feet in length.
Because of the great length of the ship it was decided to launch her sideways,—a disastrous experiment which cost the company dear. The launching ways yielded under the great weight, the ship jammed on the ways, and she had to be laboriously forced into the River Thames, inch by inch, by the aid of powerful hydraulic jacks. The great cost of the launching, which occupied two and a half months' time, caused the failure of the original company, and the ship was sold for $900,000 to a new company, who completed her in 1859. She made several voyages to America; and although in this service she was unprofitable, the great ship proved that she was staunch, eminently seaworthy, and fast for a passenger ship of that period. Although the Great Eastern was never employed on the Australian service, for which she was designed, she was usefully employed in 1865 in laying two of the Atlantic telegraph cables, and, subsequently, in similar service in other parts of the world—a work for which her great strength and size rendered her peculiarly adapted. After serving an inglorious career in the hands of the showman, the Great Eastern was sold for the value of her metal and was broken up in the autumn of 1888.
The financial failure of this ship was not due to any excessive first cost, resulting from the very thorough character of her construction, but rather to certain economic conditions of her time. Traffic across the Atlantic, both freight and passenger, was as yet in its infancy; and even if full cargoes had been available, the loading facilities of those days were so inadequate, that the ship would have been delayed in port for an unconscionable length of time. Furthermore, fuel consumption, in that early stage of development of the steam engine, was excessive, the coal consumed per horsepower per hour being about three and one-half to four pounds, as compared with a modern consumption of from one and a quarter to one and a half pounds per horsepower.
A careful study of the construction of this remarkable vessel establishes the fact that over fifty years ago Brunel and Scott Russell produced in the Great Eastern a ship which stands as a model for all time. Realising, in the first place, how vulnerable is an iron vessel which carries only a single skin, they decided to provide a double skin and construct the ship with two separate hulls, placed one within the other and firmly tied together by a system of continuous longitudinal and lateral web-plates or frames. By reference to the cross-section, published on page [83], it will be seen that the double-skin construction extended entirely around the hull, and was carried up to a continuous plate-iron lower deck, which was from 8 to 10 feet above the water-line, the distance varying with the draft of the ship. The two skins were placed 2 feet 10 inches apart and they were tied together by 34 longitudinal web-members, which ran the entire length of the double hull, and divided the space between the two skins into separate watertight compartments. These were themselves further subdivided by a series of transverse webs which intersected the longitudinal webs. The cellular construction thus provided extended from the aftermost bulkhead right through to the bow, to which it was carried for the purpose of protecting the forward part of the ship against the effect of collision with icebergs, which at that early day were recognised as constituting a serious menace to navigation. The inner skin was not continued aft of the aftermost bulkhead, for the reason that at the stern it would have been unnecessary and somewhat inconvenient.