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this is putting out of view the obvious objection to the weight destroying, as it would assuredly do, the trim of the vessel.

That this conclusion may not rest exclusively upon the above reasoning, we have ascertained the actual circumstances of the Medea, and have found that, as she stands at present, an armed frigate, she is capable of carrying a charge of 300 tons of coals; but that, if she were divested of the weight of her guns and other warlike impediments, and were adapted for a commercial vessel or à passenger packet, she would be capable of carrying 360 tons with the same displacement. Deducting from this forty tons for spare fuel, there will remain 320 tons for actual propulsion, being at rather less than a ton and a half per horse power. Now we have already shown that the estimated locomotive duty of a ton, in the outward passage, would be 1500 miles, therefore of a ton and a half it would be 2250 miles. Thus this vessel, if lightened of her arms, &c. could not carry fuel for more than about two-thirds of the passage from Liverpool to New York

Let us consider, however, the capabilities of vessels of larger tonnage having the same proportion of power, and affording the most moderate accommodation for

passengers, without

any disposable capacity for cargo. · A steamer measuring twelve hundred tons, and supplied with engines of 300 horse power, will be capable of stowing in her engine-room, and in all the other space which can be appropriated to such a purpose, at the utmost, five hundred tons of coals. With this charge of coal she will have space for an after-cabin sufficient to afford to sixty first-class passengers the same kind of accommodation as that supplied by the sailing packets. In her fore part she may accommodate bals that number of second-class passengers; exclusive of the space necessary for officers, crew, ship's stores, provisions, &c. Let it be supposed also, that the space appropriated to the fuel shall be divided and tanked in such a manner that sea water may be introduced to replace the fuel, according as it is consumed, so as to maintain the trim of the vessel and preserve

the
proper

immersion of the wheels. · If ten per cent be allowed for spare fuel, there will remain for the passage 450 tons, being at the rate of one ton and balf

per
horse
power,

which would be sufficient for two-thirds of the passage.

It is therefore demonstrable, that in the present state of steam navigation, if this voyage shall be accomplished in one uninterrupted trip, the vessel which performs it, whatever may be her power and tonnage, must be capable of extracting from coals a greater mechanical virtue, in the proportion of three to two, than

a

can be obtained from them by the combined nautical and mechanical skill of Mr Lang, the builder of the Medea, and Messrs Maudsley and Field, who supplied her splendid machinery; and this on the untenable supposition--that the average Atlantic difficulties are only equal to those to which the Medea was exposed

The frigate Medea is a vessel recently constructed, with the avowed object of imparting to her every advantage, nautical and mechanical, which the art of navigation by steam can supply. Her model has been the result of careful and anxious considere ation; her machinery the very best which the most consummate skill and inechanical talent in this country can supply, It is aided by expensive and complicated feathering paddlewheels, which, after various trials and long experience on the Admiralty steamers, are reported to give, as compared with the common wheel, cæteris paribus, an ipcreased speed, and therefore an increased locomotive duty in a higher ratio than that of four to five.*

It may be imagined that the reasoning and calculations from which our unfavourable conclusions have been deduced, are founded upon the supposition that the only propelling power is that of steam; but such is not the case. The Admiralty steamers are all rigged so as to render the power of the wind as available as that power can be to the steamer--and this is especially the case with the Medea; from which, as affording the data most favourable to the proposed enterprise, we have reasoned. That vessel has been extensively used as a sailing vessel only, the engines not being worked. In the performances, however, which have formed the basis of our calculation, sails have co-operated with steam as a propelling power..

Seeing, then, the unfavourable aspect under wbich the project of establishing an uninterrupted line of steam navigation between Great Britain and New York presents itself, let us consider whether, by resolving the voyage into the shortest possible stages, the enterprise may be brought under more promising conditions.

* For reports of experiments made with Government vessels, with a view to determine the advantage of feathering wheels, see Lardner on the Steam-Engine, p. 303. Lieutenants Potbury and Lappedge reported that the average speed of the Confiance in smooth water was increased from seven to eight miles and a half, and in rough weather from four to six miles and a half an hour. These results were obtained in two ways—first, by comparing the vessel with her own performances previously; and, secondly, by comparing her with a sister vessel running against her.-See Report of Committee on Steam Navigation to India, page 103.

Whatever difference of opinion may exist as to the practicability of an Atlantic steam voyage, it must be admitted, upon all hands, that its extent for an uninterrupled run comes to the extreme verge of the possible powers of steam navigation. In such circumstances, it would manisestly be a matter of common prudence to arrange the points of departure and arrival as near each other as the geographical and nautical circumstances of the coasts of Eastern and Western worlds will admit. For this purpose, it is obvious that the most western coast of the British Isles should be taken as a point of final departure. The west coast of Ireland would therefore naturally be selected, fringed as it is by numerous spacious and well sheltered harbours. St John's, Newfoundland, is the most western port, but this harbour is attended with so many nautical difficulties, that it could scarcely be regarded as accessible, with that certainty which such a line of communication would require. Newfoundland presents an iron-bound coast, dangerous of access; and even Nova Scotia should be avoided, were it possible to extend the passage--but the distance from the west coast of Ireland to Halifax being vearly 2200 miles, comes up to the extreme limit of a practicable steam passage; and we fear that any attempt to supersede the necessity of making Halifax a stage must be abortive. At Cape Breton, in the neighbourhood of Halifax, there are mines said to yield a species of anthracite coal well adapted for steam-boilers. The distance from Halifax to New York is between five and six hundred miles but it might be more advisable, in the case of steamers, to make the port of Boston, and leave the remainder of the journey to New York to be performed by land.

We have shown that this line of communication, if it can be established at all, must be confined almost exclusively to the transport of passengers or of light goods, which can afford to pay for expeditious carriage. We may, therefore, in this case, adopt a principle wich is never lost sight of where expedition is a permanent objectnamely, to make as much of the journey by land as it is practicable to do. The lowest rate of land travelling for passengers is nearly equal to the highest rate of steaming upon water, even under the most favourable circumstances, where the voyage is of any length; but if we bring into the account the actual existence of railroads over some parts of the proposed line, and the probable construction of them throughout every part of it, by which land can be traversed, it will afford an additional and stronger reason for limiting the water transport as much as póssible. Supposing, then, the great railroads now in process of construction, extending from the metropolis of Great Britain to its western shores, to be completed; and supposing, also, corresponding lines of railway communication to be carried from the opposite coast of Ireland, to a station for Atlantic steamers, upon its western shores, the time of transit from London to that station, even including unavoidable stoppages, would not exceed thirtysix hours; and if a reasonable allowance be made for the probable improvement of locomotive engines, even greater speed than this should be named. If the voyage from the station upon the west coast of Ireland to Halifax, a distance under 2200 miles, were performed at an average speed of six miles an hour, the average time of the trip would be 367 hours. From Halifax to New York might perhaps be performed at six miles and a half per hour, the average time being eighty-fours hours—thus the total time between London and New York, allowing one day for delay at Halifax, would be about twenty-one days. But if Boston were selected as the place of final arrival for the Atlantic steamers, a railroad being carried from Boston to New York, the time between Halifax and New York would be reduced to nineteen days and a half

This resers, however, to the average times. The influence which the substitution of land for water transport would produce upon the time of these voyages, which are greater than the average, would be much more sensible. Thus, although the average voyage from Halifax to New York would probably not exceed the time we have assigned to it, yet the voyages exceeding the average would not unfrequently amount to nearly double that time. Supposing, then, such arrangements to be carried into effect, the time between Great Britain and New York would be reduced from the present average of thirty-six days to less than three weeks.

The homeward passage, however, would not afford so favourable a comparison with the performances of the Liners. All the circumstances, which present the most formidable obstacles to the outward passage, have the effect of giving advantage to the powers of the steam over those of the sailing vessels; while, on the homeward passage, these circumstances are precisely reversed-having a direct and powerful tendency to diminish the advantages of the steamers, and to reduce them more to the level of the sailing vessels. With a strong and continual favourable wind, a sailing vessel, built as she is expressly to avail herself of that impelling power, and unobstructed by any external impediments to her passage through the water, is under the most favourable possible circumstances for speed. On the other hand, a steamer is in a great degree shorn of her powers. The question, indeed, is whether, under all circumstances, her average homeward passage would be as expeditious as that of a vessel constructed expressly and exclusively for sailing. We have seen that the average homeward passage of the Liners is nineteen days and seven hours; or 463 hours. Taking, as before, the distance traversed as 3200 miles, the average rate would be about seven miles per hour; being very nearly equal to the greatest average speed obtained by the Medea under the most favourable circumstances, where the steam power was aided to as great an extent by sails as wind and weather permitted. But the case of the passage by steamers will present itself under an aspect still more unfavourable, if a station for sailing vessels should be established

upon

the west coast of Ireland, which would be almost the inevitable consequence of a railroad being carried across that country. A considerable part of the time of the voyage of the sailing vessels is spent in navigating the channels, so that their average rate would be considerably increased is, instead of making Liverpool, they should terminate their voyage on the west coast of Ireland. Let it be remembered that this is a case in which the question of cargo cannot be raised. It is quite true that no railroad accommodation which could be afforded through Ireland would induce the disembarkment and reshipment of a cargo of heavy and bulky merchandise; and that, notwithstanding the facility and expedition of land transport, the vessels carrying cargo would for the most part still navigate the channels to the British ports. But we have seen that the steamers, if they can be established at all, must be confined chiefly to the transport of passengers, and the sailing vessels competing with them can be only the Liners; or vessels limited in the same manner as to their objects of transport. It is to us then quite apparent, that in the event of an Irish railroad and the competition of the Transatlantic steamers, the sailing vessels carrying passengers only, or light goods, would of necessity avail themselves of the same western ports of these countries; and the comparison of time between two classes would of course be then less favourable to the steamers than we have stated it.

Let us not, however, be misunderstood. That the passage from Liverpool to New York cannot, on any occasion, be made in one run by a steam-ship we do not maintain. Our reasoning is founded on numerical data, taken from the averages of long continued performances, as well of steamers as of sailing vessels; and to average cases only can our conclusions be legitimately applied. The average time of the outward voyage to New York is thirtysix days; and we say that when the circumstances of wind and water are such that a sailing vessel would require that time to make the passage, a steamer cannot make it without an intermediate supply of fuel. But it very frequently happens that the time of the outward passage of sailing vessels is less than thirty

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