THE series of Exhibitions held in London during the last few years would certainly have been incomplete without one to illustrate the history, development and progress of the Navy. Such an under- taking could not fail to enlist public sympathy and support; partly on account of the warm corner the Navy has won and continues to hold in the national heart, and partly from the extraordinary nature of the development and progress that has taken place in it during the last half century, which may indeed be almost more correctly described as a metamor- phosis.

The lesson to be learned by a careful study of the models in the Sepping Gallery may reasonably be divided into three sections; first, the period when sails were the motive power of our ships extending from the historical Great Harry, a " first-class battle-ship " in the time of Henry VIII., to the Queen, one of the finest three-deckers in existence in 1845, when the irrepressible steam-engine was just beginning to push itself into pro- minent notice as the coming motive power of ships both for war and com- merce. The second section, which was short but full of rapid change, in- cludes the period during which steam and sail worked amicably together in propelling our war-ships; progress here : marched with giant steps, from the old paddle-wheel sloops, in which steam was the principal propelling power, to the screw propeller which for a time tended to equalize the value of the two powers, because the application of the latter did not entail any change in the form of the vessel from that best applicable to sails, as was the case with the paddle-wheels.

The screw could also then be lifted out of the water when sails were to be used, leaving the ship a perfect sailing-ship.

The contest between wood and iron as the material of which to construct the ships also commenced about this time, ending, in the first place, in a complete victory for wood, to be soon followed by a com- plete rout and the general adoption of iron, to be in its turn followed by steel. Then the metamorphosis may be said to have begun, and the third section, or that in which the use of sails was entirely aban- doned in favour of steam, asserted itself.

One step that hurried on the inevitable change was the introduction of armour plating. A remarkable illustration of this march of time is displayed by the model of the present Sans-pareil, one of the most powerful of the war-ships of to-day, compared with the drawing of her predecessor, the first screw line-of- battle ship—built about 1849—hanging near it. their quaint names of "The Mariner's Mirrour," "A New Sea Atlas, or Water World," "The Lightning Colomne, or Sea Mirrour," which are supplemented by a chart, lent by a private exhibitor, showing the track of Sir Francis Drake, •with his fleet of twenty-three ships, to the West Indies and back between Sep- tember 1585 and July 1586, and followed up by charts and original surveys of different parts of the coast of England, as well as other parts of the world, down to the latest survey by H.M. surveying ships, and specimens of the copper plates from which the Admiralty charts are printed.

To notice even very briefly all the other interesting exhibits of chronometers, com- passes, instruments for observing the sun, sounding machines, &c., would demand very much greater space than we have at our command; we must therefore content ourselves with remarks on their complete- ness and power for instruction and interest to an ordinarily careful observer. We must now pass on to the exhibits of the Elder Brethren of the Trinity House and the Commissioners of Northern Lights, i.e., the Lighthouse and Ship Authority for Scotland. Here we find represented the first Eddystone Lighthouse, which was proposed to the Trinity House in 1691, and erected by the designer, the light being first exhibited in October, 1698.

The following year he strengthened the tower and raised it 40 feet, making the total height 120 feet. Its life was not a long one, however, as it was completely destroyed during the great gale of the 26th of November, 1703, when the talented designer, who happened to be there at the time, lost his life, together with some workmen who were with him and the light-keepers. This lighthouse was re- placed by a wooden structure, with its base built round a solid core of granite 24 feet high, the whole height being 92 feet. This building was designed and completed by a silk mercer in London, assisted by two experienced shipwrights from Woolwich Dockyard, and the light, which consisted of twenty-four candles, These remarkable changes are not con- fined to ships of war, for the Sepping Gallery contains many beautiful models of the modern passenger steamer, showing quite as great an advance in construction as the men-of-war. The most striking illustration of this part of the subject is to be found in the exhibit of the Peninsular and Oriental Steam Navigation Company, standing in a kiosk by itself, in which are shown models of four of the newest representations of this magnificent fleet, together with one of the first steamers possessed by the Company, and used for the conveyance of the mails, which can only be designated as a pigmy by the side of its giant successors. Although these vessels are primarily constructed for the purposes of peace and commerce, are capable of being armed, not only for their own defence, but for taking a very impor- tant part in those operations of war for which their great speed and other qualities eminently fit them, viz., the protection of our commerce from the depredations of swift, lightly-armed cruisers of the enemy, keeping open communications, &c.

At the head of the Sepping Gallery, running across it, or, rather, connecting it with the Howe Gallery and reached from either by a flight of steps, is the Cook Gallery, containing very interesting and instructive exhibits of the Admiralty, the Trinity House, the Meteorological Society, and the ROYAL NATIONAL LIFE- BOAT INSTITUTION, as well as many private exhibits. The exhibits of the four named are full of interest for a similar reason to that given in the case of the exhibits in the Sepping Gallery—viz., the complete illus- trations they produce of the development and progress of the subjects to which they belong. The charts exhibited by the Admiralty comprise a collection of Porto- lani, dated about 1530, exhibiting the world as then known, on Ptolemy's pro- jection, and showing Magellan's track from 1519 to 1522. Next comes the first printed edition of Ptolemy's Geography, dated 1533, and other old charts of the sixteenth and seventeenth centuries, with was first exhibited in 1708. This light- house was destroyed by fire in 1755, the keepers being rescued by boats from the shore. The next in order was Smeaton's famous lighthouse, which was replaced ten years ago by the present one, a full- sized model of which stands in the grounds, rearing its proud head above everything else; and most appropriately placed at its side is the old Crescett-burner, or grate, from which a coal fire was burnt at St. Agnes, Scilly, from sunset till sunrise in 1680.

One very ingenious exhibit in this gallery is the two working models illus- trating the currents in the Atlantic and Indian Oceans respectively, of course including the far-famed Gulf Stream, which is credited with so much influence on the climate on the western and north- ern shores of these islands. In this gallery also stands the counter of the Royal National Life-boat Institution, dis- playing models of the different types of life-boats most generally in use at its stations and comprising the newest type of self-righting sailing life-boat, fitted with two drop keels, water ballast and all the other improvements of which experi- ence has taught the advantage. Near to this model is the newest type of self-right- ing pulling boat and its elder sister, the non-self-righting sailing life-boat, to which the men on a part of the coasts of Norfolk and Suffolk are so devotedly attached; and not without reason, for they have done noble work with them in saving life on that dangerous coast. Each type of boat has its partisans and admirers, who are always ready to face any wind and sea in them when the call for help comes, and both have done equally good service.

These columns would not at any time be the place in which to criticise the merits of either type, because both are recognised by the Institution as efficient life-boats and have, as before stated, their ardent ad- herents ; but it would be particularly out of place to do so now, as the arrangements are just completed for carrying out exhaus- tive trials between them during the coming winter to prove their relative values in the different circumstances in which they may be called upon to carry out their work of saving life from shipwreck.

The model of the safety fishing-boat is a lasting memorial of a most beneficial movement, in which the Institution took the initiative about twenty-six years ago, ! to bring about the introduction of decks in the large herring-boats, most of which, particularly in Scotland, were then wholly open boats; now such a thing is not to be seen and the increased safety in bad weather, as well as the comfort to the crews, must be self-evident.

The strongest proof that the march of development and progress before dwelt upon is not absent from the affairs of the Life-boat Institution is to be found on this counter in the model of the steam life-boat, brought out last autumn by the Institu- tion. She has been stationed through the winter at Harwich, where she has been thoroughly tried in bad weather and heavy seas and has proved a complete success, having already contributed to the saving of thirty-three lives. It is a great pity that the expenses of both building and maintaining such a boat are so very large as to prove a bar to their extended use for service on outlying sands, to which they are so admirably adapted.

Passing from the Cook Gallery through the Howe and Nelson Galleries, we come to the Franklin Gallery, with its touching collection of relics of the ill-fated Arctic Expedition of 1844, under Sir John Frank- lin. The pictures hanging on the walls, and the admirably designed figures with sleighs and tent bring forcibly before the observer the hardships and risks of this service generally, and cannot but lead to the conviction that this is a work of all others demanding a sound mind in a sound body as well as a stout heart for its proper performance. The play - bills, numbers of the " North Georgian Gazette," 1820, "Arctic Miscellanies," 1850-51, " Illustrated Arctic News," 1850-51, and the songs printed on board, show that it was not " all work and no play," but it must be difficult to those who have  not experienced an arctic winter to realise what it means, and the necessity for every available source of amusement being promoted to the utmost. Close to these relies stends the model of the cairn in which the cylinder was found that gave the last-written information of the monu- ments of the then survivors of the ill fated expedition as well as the date of Sir John Franklin's death.

It is rather remarkable that this and other important relics were not discovered by any of the expeditions previously sent oat by the country to search for the missing expedition, but that to do so fell to the lot of the gallant little ship Fox, •which comprised a private expedi- tion, fitted out by Lady Franklin and ; her friends, the command of which was entrusted to the well-known Captain, now Admiral Sir LEOPOLD McOuNTOCK, K.O.B,, TT.B.S., the sledge which he actually used in his land journeys being one of the two exhibited..