1864. | Samurtson on Steam Navigation. 245 
of the average price paid on the voyage to Australia for ordinary 
steamers, she would be worked with far greater economy than other 
boats, besides making the voyage in a much shorter period. It was 
with this object that the ‘Great Eastern’ was projected. 
This gigantic vessel was constructed by Mr. John Scott Russell, 
under the superintendence and direction of Mr. Brunel; her prin- 
cipal dimensions being 691 feet extreme length; 680 feet between the 
perpendiculars; breadth across paddle-boxes, 118 feet; breadth of 
hull, 83 feet; depth, 58 feet; and her tonnage by the old measure- 
ment, 22,500 tons; she has stowage for 6,000 tons of cargo, and her 
coal-bunkers will hold 12,000 tons. She is built on what is termed 
the cellular principle, being similar in construction to the tubes of 
the Menai Bridge, so that she is virtually a double ship, or one vessel 
placed inside of another, with partitions running fore and aft between 
her two “skins.” She is divided into twelve water-tight compart- 
ments, and the weight of iron in the hull is 8,000 tons. She is pro- 
pelled by a combination of paddle-wheels and screw. The engines 
for working the paddles consist of four oscillating cylinders 74 inches 
diameter and 14 feet stroke, each cylinder complete weighing 38 tons ; 
they are of 1,000 nominal, or 3,558 indicated horse-power. The 
paddle-wheels are 56 feet diameter, and the floats are 15 feet by 3 feet, 
and 30 in number. The screw-engines consist also of four cylinders 
86 inches diameter and 4 feet stroke, and are of 1,600 nominal, or 
4,610 indicated horse-power; the screw is 24 feet diameter, and 
44 feet pitch. The boilers for this stupendous machinery are ten in 
number, each boiler weighing upwards of 50 tons; four of them drive 
the paddle-engine, and six the screw. She has also powerful auxiliary 
engines for turning the screw when under sail, and has no less than 
ten donkey-engines for pumping, and for various other purposes. 
She possesses accommodation for 800 first-class passengers, 2,000 
second-class, and 1,200 third-class; and her principal saloon is 100 feet 
long, 36 feet wide, and 13 feet high. The consumption of coal 
amounts to 12¢ tons per hour, and the greatest speed by paddles 
and screw separately is as follows :—Paddles alone, 8 knots; screw 
alone, 9 knots; giving the screw a decided preference over the paddles. 
The cubic feet in paddle engine-room, including boiler space, is 
116,000; and the cubic feet in the screw engine-room, including boiler 
space, is 112,000; mean draught of water, 23 feet 85 inches; mean 
effective diameter of paddles, 48 feet 7$ inches ; mean slip of paddles, 
17-4 per cent.; mean slip of screw, 17-9 per cent.; mean consumption 
of coal per hour, 12+ tons; mean miles per hour, 14713; coal consumed 
per indicated horse-power, 54 lbs.; ditto per nominal horse-power, 
112 lbs.; greatest distance run in 24 hours, 360 miles; mean revo- 
lution of paddles per minute, 10%; of screw, 563; mean displacement, 
19,2733 tons; or, with 5,000 tons of coals on board at 24 feet 
10 inches draught, 20,940 tons. 
As a specimen of expert workmanship and strength the ‘ Great 
Eastern’ has never been excelled. 
The following particulars of length and beam of some of the 
VOL. I. s 
