The ship have any advantage over the Kent,' but rather the reverse." "Kent" was telegraphed in the Downs one day before the "Marco Polo" was sighted from Holyhead-the distance to the Downs being 165 miles or thereabouts greater than to Holyhead. This is one example of the great value to be attached to superior skill for conducting composite sailing, in which both captains were possessed of more than the ordinary amount of ability. If we judge from Captain Coleman's account, the " Kent" is a ship that should have made the voyage from Australia in ten days less than the "Marco Polo;" instead of which, allowing one day for the difference of distance of the Downs and Holyhead, still the "Marco Polo" accomplished the run in three days less time.

When first the admiralty did me the honour to publish my tables, I anticipated a greater amount of improvement from its application to what I denominated windward great circle sailing than from any other of its practical uses. Although with respect to composite sailing it has been employed with a degree of success surpassing my most sanguine expectations, still, in working a ship to windward, in very few instances am I aware of its having been brought into application. The case I have just given of the Marco Polo" leaving Melbourne is a fine illustration of this application, and is in fact the idea which suggested itself to the mind of Captain Forbes when he made the boast, which has subjected him to animadversion, that he would turn a foul wind into a fair; for practical purposes, he has kept his word. Windward sailing [ thus describe:

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When a ship cannot, on account of adverse wind, sail directly to her port, she obviously ought to be put on that tack by which she nears her port by the greatest proportion of the distance sailed. It is also evident that she must do this when her track deviates by the least amount from the direct line which connects her with her destination; or, in other words, when she is put on that tack which deviates less from the true course than the other tack. In adopting this rule it must however be especially borne in mind, that the true course alone can serve as a guide in choosing the tack; and that the great circle, and not the rhumb, is this true course. But, since the mariner is more conversant with the rhumb than the great circle, too much attention cannot be directed to the importance of making this distinction between these two courses in connection with windward sailing. In crossing the Pacific, the rhumb course frequently deviates four points from the true course: under such circumstances it is impossible that the mariner can navigate his vessel with advantage if he fail to make himself acquainted with the great circle course.

The term "windward great-circle sailing" is employed with special reference to these facts. This new form of describing the application of the true course is rendered necessary on account of the prevalent erroneous opinion-that "to a sailing vessel great circle sailing is of comparatively little value;" and that "steamers, being in a measure independent of the winds, could more readily than sailing vessels avail themselves of the advantages of great circle sailing." The reverse is the fact to a sailing vessel, the advantage of being guided by the true course, when contending with adverse winds, is fourfold as great as that which is conferred on a steamer. Thus, for example, the increase of distance arising from the direct track being diverted two points is only 1 mile in 12: but if a ship that sails six points from the wind deviate two points further from the angle of the true position of her port on account of the wrong tack being chosen, she cannot in the least degree near her port; whilst, under the same circumstances, the knowledge of the true course would enable the mariner so to choose his track as to make good 84 miles by a run of 12 miles.

The rule for windward great circle sailing is as follows:-Ascertain the great circle course, and put the ship on that tack which is the nearest to the great circle course.

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We can give no better illustration of an extreme case of this application of great circle sailing than that already given of the Marco Polo" leaving Melbourne. Had that ship stood on the port tack 1000 miles, with the wind S.E. by E. she would have neared the Horn 874 miles; whereas, if the "Kent" had stood 1000 miles on the starboard tack, she would have been 200 miles further off from the Horn than when she started, although by the chart the reverse appears to be the case. To make use of the words of the Hydrographer in reference to this subject, this principle is valuable "not only in those strong and glaring cases where a large amount of distance may be obviously saved, but in the more everyday work of selecting the most advantageous tack on which to lay the vessel with a foul wind." Scarcely have I examined a chart or a log-book without perceiving that this is not perfectly understood. I am frequently informed that they could not get so far south as their intended maximum latitude. Now this is an impossible occurrence with a ship of ordinary weatherly qualities. If the wind be less southerly than E.S.E., she would undoubtedly do better on the port tack till she got into the regions of the N.W. trades; if more southerly, she could make easterly on the starboard tack.

In a New York voyage, if head winds prevailed, I proved seven years since that three days might be saved; and yet I have no reason to

believe that in such voyages it has ever been adopted, except by Captain Reed, of the "Iowa," in a late voyage. The success of this one trial was quite equal to that which I had anticipated.

Until within a few months the principles we have explained, and which have been employed with such signal success by sailing vessels, have been totally rejected in navigating steamers to Australia. I had promised to this Society a Paper on the best route for steamers to and from Australia, but now it is unnecessary; the "Harbinger" and "Argo" have solved the problem, and I hope that in a few weeks news from the Great Britain will confirm the fact. Up to within twelve months, steam to Australia might be regarded as a failure; that is, sailing vessels having made the direct passage in less time than steamers, we could not regard steam as a successful experiment in such voyages. The causes I consider to be, first, that the commanders have been bound, by contracts entered into by the directors of the companies to which their ships belong, to land mails or passengers at intermediate places which, on the chart, appear on the route to Australia, whilst, if they had consulted the winds and the globe, they would have perceived that such intermediate stations were undesirable; and secondly, that the previous experience of those in command of ocean steamers had led to a system of practice unsuitable to the management of steamers bound to and from Australia.

The principle ocean steamers had made their voyages within the regions of the variable winds: the consequence is, that in such cases the wind is disregarded in selecting the route, and out and home these steamers have been navigated by the shortest route. When the winds have been favourable, the sails have been employed; but when the wind is adverse, it is steamed up against. No other practice would be successful in these regions of variable winds; but in a voyage to Australia, in a route of upwards of 13,000 miles, steam is only required for about 3000 miles if the tracks of our sailing vessels be adopted. But instead of being guided by the winds we hear of one vessel, in steaming up against the winds, reduced to the necessity of falling to leeward for coals. Then, again, because by the Cape it is about 7 per cent. shorter than by the Horn, they have returned as well as gone by that route. Then, again, we have instances of three coaling stations out, and three coaling stations home; so that, if we allow four days for coaling, from this cause alone twelve days on each passage has been wasted. At length sailing vessels taught steamers to return by the Horn, and then the challenge was thrown in Australian newspapers in these words"Steam-ship Cleopatra,' guaranteed quickest route home." "Steam

to England from the colonies on the 28th July, 1853, via Wellington (New Zealand), calling at Rio Janeiro and Madeira." Here we have three coaling stations; and how situated? After steaming about 1200 miles to Wellington, I suppose we should find that she had neared the Horn about 300 miles. Having arrived at Rio, she will have the whole force of the north west trades to contend against. I am not aware of the number of days her voyage occupied; but if the prospect held out be realised, it is a different result to that which I should have expected.*

The advice which I have given is to coal on the outward voyage at Bahia, and on the homeward voyage at the Falkland Islands. This route has been successfully followed out in each particular but that calling at St. Vincent instead of Bahia; and for this alteration there is a valid reason, the state of health at Bahia or Rio. If a coaling station on the homeward voyage be required, the Falkland Islands are undoubtedly the best calculated for that purpose. Under such circumstances my advice would, in order to make the shortest voyage out and home by the aid of steam, be as follows:--

By the aid of both steam and wind, proceed to St. Vincent with as great despatch as possible; for economy of fuel is not of so much importance in the first part of the voyage, since it is not probable that more than one-third of the coals which the whole voyage will require will be consumed between England and the Cape de Verd. At this station, having taken a fresh supply of fuel, sail to the calms direct, and until you reach the latitude of 48° use steam freely whenever it is required. By so doing, you will not only make your passage more rapidly, but you will lighten your ship by the time you have reached the regions in which you will depend on sail alone. The course you should take after you leave St. Vincent, should be such as would take you as far at least as 20° west, at the point where that meridian crosses the 30th parallel of south latitude. But should the winds be such as would take you across that parallel at 30° west, you will have lost little by crossing at that point; at least, you will have done better than by not having sailed free through the south-east trades in order to get further east. Between 30° and 48° latitude on the great circle of 50° you will have occasional use for steam. If required, coals could be obtained for steamers at Kerguelen's land, no more expense being required than labour and the most simple machinery. This island, being nearly broken through the centre by the action of the ocean, has

The "Cleopatra" arrived at Liverpool, February 24, 1854, after a voyage un precedented in length for a vessel returning from Australia by the Horn.

its coal strata exposed to the light of day.

After passing Kerguelen's land it is very improbable that steam will be required for seven hundred miles. On your return by the Horn I doubt whether more than a half cargo of coals should be taken on board, since between Australia and the Falkland Islands not more than 1500 miles would require the use of steam. A full cargo would tend only to burden the ship whilst under sail, and thus lengthen the voyage instead of aiding the ship. From the Falkland Islands, with a full cargo of coals, you should strike off on the same great circle by which you left your highest latitude, and then economise your fuel, taking advantage of the N.E. trades, and taking care to reserve a supply of coals for the variables, and especially for the channel.

There is, however, another problem which remains to be solved, for which the experience of steamers on the composite routes will soon furnish us the data. Is it desirable that steamers should have any coaling station on the voyage out and home? The number of days during which such steamers as the Great Britain would require steam out or home, I consider, will prove to be about 20. Now, at neither station, either out or home, is more than one-third of the total amount of coal required. Then, by decreasing the amount of coals required by the engines to two-thirds the present amount, we should decrease the power of the engine one-third. But this decrease of power would increase the time required to steam across the regions where the aid of steam is wanted more than from 20 to 24. Then, if one-third the coals is expended in increasing the speed of the vessel so as to save the time lost in coaling, we cannot regard such an expenditure in any other light than a waste. Before, however, we can establish such a proposition as a fact, further data are required.

When reviewing the passages of steamers in comparison with sailing vessels, we have regarded them as failures up to a very recent period. This term must be taken in a restricted sense. In one respect steamers have been superior, in contributing to the health and comfort of the passengers. No one but those who have crossed the tropical calms can form a perfect idea of the distressing feelings they give rise to. With a tropical temperature there is an incessant roll which frequently in these climates affects even the experienced seaman, but to the landsman it is unbearable. Under these circumstances the sickness and fever arise; and to bear out this opinion we have the fact that the mortality of passengers on board the steamers that cross the line is only ten per cent. of the proportion of that experienced by those on board of sailing

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