"And at SIXTEEN MILES per hour there will be no displacement available for mercantile cargo.
"Hence, it appears, that for voyages of 1,000 miles and upwards, without re-coaling, the speed of ten nautical miles per hour would involve about double the cost per ton of eight miles, and may, therefore, be regarded as the extreme limit that can be generally entertained for the mercantile purpose of goods' conveyance; and that the attainment on long passages of a higher rate of speed than ten miles (though admissibly practicable) would involve obligations altogether of an exceptional character, such as the special service of dispatches, mails, passengers, specie, and the most valuable description of goods can only meet."
SECTION V.
OCEAN MAIL STEAMERS CAN NOT LIVE ON THEIR OWN RECEIPTS.
INCREASE OF BRITISH MAIL SERVICE: LAST NEW LINE AT $925,000 PER YEAR: THE SYSTEM NOT BECOMING SELF-SUPPORTING: CONTRACT RENEWALS AT SAME OR HIGHER PRICES: PRICE OF FUEL AND WAGES INCREASED FASTER THAN ENGINE IMPROVEMENTS: LARGE SHIPS RUN PROPORTIONALLY CHEAPER THAN SMALL: AN EXAMPLE, WITH THE FIGURES: THE STEAMER "LEVIATHAN," 27,000 TONS: STEAMERS OF THIS CLASS WILL NOT PAY: SHE CAN NOT TRANSPORT FREIGHT TO AUSTRALIA: REASONS FOR THE SAME: MOTION HER NORMAL CONDITION: MUST NOT BE MADE A DOCK: DELIVERY OF FREIGHTS: MAMMOTH STEAMERS TO BRAZIL: LARGE CLIPPERS LIE IDLE: NOT EVEN THIS LARGE CLASS OF STEAMERS CAN LIVE ON THEIR OWN RECEIPTS: EFFICIENT MAIL STEAMERS CARRY BUT LITTLE EXCEPT PASSENGERS: SOME HEAVY EXTRA EXPENSES IN REGULAR MAIL LINES: PACIFIC MAIL COMPANY'S LARGE EXTRA FLEET, AND ITS EFFECTS: THE IMMENSE ACCOUNT OF ITEMS AND EXTRAS: A PARTIAL LIST: THE HAVRE AND COLLINS DOCKS: GREAT EXPENSE OF FEEDING PASSENGERS: VIEWS OF MURRAY AND ATHERTON ON THE COST OF RUNNING STEAMERS, AND THE NECESSITY OF THE PRESENT MAIL SERVICE.
From the foregoing Section it is evident that the cost of running ocean steamers is enormous, and that in the chief element of expenditure it increases as the cube of the velocity. This, although true, is certainly a startling ratio of increase, and calculated to arouse attention to the difficulties of postal marine navigation. Seeing that ocean speed is attainable at so high a cost, we naturally conclude that fast mail steamers can not live on their own receipts upon the ocean.
Since Great Britain established her first ocean steam mail in 1833, she has gone on rapidly increasing the same facilities, until her noble lines of communication now extend to every land and compass every sea. The last great contract which she conceded was last year, to the "European and Australian Company," for carrying the mails on a second line from Southampton via Suez to Sydney, in Australia, at £185,000, or $925,000 per year. And although her expenditures for this service have gradually gone up to above five millions of dollars per annum, she continues the service as a necessity to her commerce, and a branch of facilities and accommodations with which the people of the Kingdom will not dispense. The British Government set out with the determination to have the advantages of the system, whether it would pay or not. They believed that the system would eventually become self-supporting, by reason of the many important improvements then proposed in the steam-engine, and they have ever since professed to believe the same thing. But their experience points quite the other way; and while the service is daily becoming more important to them in every sense, it is also becoming year by year more expensive.
Contracts which the Admiralty made with several large and prominent companies in 1838 they renewed at the same or increased subsidies, after twelve years' operations, in 1850, for another term of twelve years. And so far from those companies with their many ships on hand being able to undertake the service for less, they demanded more in almost every case, and received it from the government. The improvements which they anticipated in the marine engine were more than counterbalanced by the rise in the price of fuel and wages all over the kingdom and the world. In fact, those improvements have been very few and very small. It still takes nearly as much coal to evaporate a pound of water as it then did; and the improvements which have been made were generally patents, and costly in the prime cost of construction to a degree almost preclusive of increased benefits to the general service. At any rate, the latest steam adaptations and improvements have proven unequal to the end proposed, and the cost of the ocean service is now far heavier than it ever has been before, simply because of the greater speed required by the public for the mails and passage.
It had long been hoped that this difficulty of increasing cost in running ocean steamers might finally be overcome by another means; and the whole available engineering and ship-building talent of Great Britain and the United States has been directed not entirely to the engine department, but to the hulls and to the production of a large class of ships, which are admissibly cheaper in proportion to size and expense of running when compared with smaller vessels, if they are always employed and have full freights and passage. It is well established that large steamers run proportionally cheaper than small ones. (See [Table III.], page 76.) This arises from the important fact that the length increases far more rapidly than the breadth and depth. Consequently the tonnage of the vessel increases much faster than the resistance. In passing through the water the vessel cuts out a canal as large as the largest part of its body, which is at the middle of the ship. If the vessel be here cut in two, the width and depth, or the beam and hold being multiplied together will give the square contents of the midship section. Now, when a vessel is doubled in all of its dimensions, this midship section and consequently the size of the canal which it cuts in the water, does not increase as rapidly as the solid contents of the whole ship, and consequently, as the tonnage. Hence, the resistance to the vessel in passing through the water does not increase so rapidly as the tonnage which the vessel will carry.