A great naval Power, and especially a Power which relies upon its Navy to the comparative exclusion of military pretensions, must needs keep its Fleets at sea. In some form and upon some system or other the British flag must be borne on foreign waters for the protection of British commerce, the assurance of British interests, and the maintenance of the British name. On some system, too, that seamanship and discipline which active service alone can impart must be acquired by our officers and men. Hitherto, the requisite provision in this direction has been made, if not on judicious principles, at any rate with no niggardly hand. Our foreign squadrons have been large and numerous. They were dispersed all over the world, nor was there a spot on the globe where a British man-of-war was not usually at the service of a British settlement. Not a Consul but could summon a gunboat to his aid in case of need; and yet it was argued that, while we were keeping so many ships at sea, we were doing next to nothing for the proper training of those who in any emergency would man our vessels and command our Fleets. It was not by cruising in quiet seas or lying in quiet harbours that good sailors were to be formed. Some more trying duties were required for that purpose, and the reader may possibly recollect that periodical voyages to the two Poles in search of what might be found there were recommended as necessary expeditions if the British Navy was to be kept up to the mark in adventurous enterprise and professional ability. Now, if a Fleet is sent to circumnavigate the globe, it must needs encounter its share of those trials by which seamen are manufactured and proved. A voyage round the world is no longer such an exploit as it was in the days of Anson, but it is still not impossible that a British squadron may return, as Anson did, with a reflection of lustre and credit on British power.

Of course it will have been discerned that if economy as well as practice is in view, our whole system of foreign squadrons must be modified in proportion to the new outlay upon a roving Fleet, and this, in point of fact, has been done to a great extent already. Those squadrons have been materially reduced, and the question is whether the reduction cannot he carried still further. There are stations, beyond doubt, where a permanent force may be indispensable, and where the objects in view could not be secured by the occasional visits of a Flying Squadron. But there are others where no such establishments are necessary, and these may be found, perhaps, to be more numerous than we imagine. It must not be forgotten that in the present day the agency of the electric telegraph has revolutionized the work of Naval Administration. A few hours would suffice for the despatch to any spot of a Fleet far stronger than any force that could be kept permanently on the station. To be weaker altogether and yet always stronger at a given point is the best evidence, as it is the chief object, of successful strategy. By concentrating our forces in one or two powerful squadrons available for service in any direction, we may do far better than by scattering our ships over half the world. That at least is the presumption which commends itself to naval reformers. It was asked one night in the House whether the Admiralty would know where its Flying Squadrons were to be found, and whether it would be able to communicate with their commanders as circumstances might require. We cannot suppose there will be much difficulty in making due arrangements on this head, or that our position will not, at any rate, be as good as before.

Over and over again we have been told that in the event of a war half our vessels on foreign stations could do nothing better than run for safety to a British port. A Flying Squadron, however, would always be strong enough to hold its own, as well as to carry assistance to one point or another.

It deserves to be noticed that the Americans not only despatched the expedition of which we have spoken, but regarded the results with extraordinary and unqualified approval. The Secretary of the United States' Navy declared in his Report that the ships of the Union had never performed a more successful cruise, and that the whole proceeding had redounded to the credit, reputation, and glory of the country. No better investment, according to this Minister's statement, had ever been made than in this naval demonstration. We do not anticipate any such remarkable consequences from our own expedition, nor, indeed, are we under any necessity to produce or revive impressions of our ubiquity or power. But we trust we may reckon on results conducive to the true efficiency of our Navy, and we are willing to hope that the experiment in point of economy also may be found to succeed. If the Estimates are ever to be materially reduced, it must be by the adoption of a reformed system of administration in such matters as these.

The Pearl, 17 guns, 400-horse power, unarmourcd screw corvette, Capt. John F. Ross, arrived at Spithead early yesterday forenoon from Plymonth Sound, and on anchoring saluted the flag of Admiral Sir James Hope, G.C.B., Port Admiral and Naval Commander-in-Chief, the salute being returned by the Admiral's flagship in Portsmouth Harbour, the screw three-decker Duke of Wellington, Capt. George Hancock. During the forenoon Admiral Sir James Hope embarked on board his steam yacht the Fire Queen, and proceeded to Spithead, where he made an official inspection of the Pearl and of her crew at general quarters, preparatory to the ship being taken into Portsmouth Harbour to be dismantled and paid out of commission.