Dieppe section of the Channel is properly a sectional tide. The action of this sectional flow and ebb is traceable as far up the Channel as Christchurch, where the flood tide takes place about 3 hours after the Portland and Alderney, or about the half ebb of those tides, and shows the state of the Alderney low-water mark very distinctly.

The contrast of the lower and upper channel waters is very remarkable: on the same day that the Brighton waters ebb from 9h 0m a.m. to 3h 10m p.m. the Plymouth waters rise from 9h 17m a.m. to 3h 27m p.m. It is very observable, also, that from this combination of the tide-waters in these two basins, there is always a double flow of tide to be obtained by ships in going up the Channel; so that if a vessel could leave Plymouth with the first flowing of a tide from that point, it would fall in with another young tide, after a six hours' voyage, about the Channel Islands, which would carry it up the upper channel for another flow. The distance is not above 80 miles, and it might be accomplished by a steamer, so that if such a vessel fell in with the flow of the tide in the meridian of Plymouth at 9 o'clock a.m., and reached that of Alderney at 4 p.m., it would find the ebb from that high water flowing into the Brighton Channel as a young tide, which would carry it to its flood after another seven hours' voyage. To take the benefit of that flow, however, the vessel should keep on the French side of the Channel from the Alderney waters, as we should keep the English side in a returning voyage.

Having thus traced the gyrations of this great Atlantic wave in the Channel basin below the line of division between La Hogue and Portland Head, and shown the bank of head-waters established with its broken momentum between the Dorset and French headlands, we will proceed to show the tidal operations in the upper channel, in connection with this disposition.

It must here be borne in mind, that the upper or Brighton and Dieppe channel, which embraces the Portsmouth waters, does not depend wholly upon the western or Atlantic tide for its supply; but derives one-half of its waters, or some other proportion, from the North-Sea tide, through the Straits of Calais and Dover. The flow of waters sets in to the Upper Channel from those two opposite points, at nearly the same hour. It is low water at Calais at 4 o'clock, p.m., the same day that it is high water at Guernsey and Alderney at 4h 30m p.m. At Dover the low water is forty minutes earlier than at Calais; the waters begin to flow into the Channel, therefore, about four o'clock from the Dover Straits, and about half-past four o'clock from the Alderney Head waters: the difference is, that the western flow comes by the fall of a head of waters, or ebb of the encaged wave of the ocean-tide from the Atlantic, while the eastern supply is by the natural flow or rising of the North Sea tide at that point, where it enters the Channel. The Alderney tide falls half the height of its full elevation above the ocean low-water; and the North Sea, being a sectional tide itself, rises half only of the full elevation of the ocean waters, from which it is derived. The rise and fall of the opposite sources will, therefore, equal one another, and afford a mean elevation at the end of their period of flooding. The adjustment of this counter-flood from the two seas is again very extraordinary, for the North Sea waters appear to keep their course along the north side of the Channel, and those of the western waters

along the south or French side; at least the entering of the tides on the two coasts move in that order, and in the reverse way to each other.

Their sequence is as follows: on the French coast, having a high water at the Alderney Pier at 4h 30m p.m., the high water will follow at Cherbourg at 5h 23m p.m.; at Havre de Grace at 8h 10m p.m.; at Dieppe, more east, at 9h 23m p.m.; at Boulogne at 9h 44m p.m.; and at Calais at 10h 6m p.m. On the other side of the Channel, the Dungeness tide, which precedes the Dover tide by about a quarter of an hour, will have had its ebb, or beginning of flow, about 3h 0m p.m. on the same afternoon, and its flood at 9h 10m. At Beachey Head the same order will be observed, eighteen minutes later, or with its high water at 9h 28m p.m.; at Brighton, nine minutes after Beachey Head, and at Shoreham and Selsea Harbour, eight minutes later; making the high water of those two places at 9h 45m, which is the period that the counter-flow carries the high tide up to Boulogne, whose tide we have seen is at 9h 44m. The mean point of the two floods appears to be about Dieppe and Beachey Head, where the high waters occur about the same time, viz., about 9h 25m p.m. The cause of a set of the North Sea waters towards the north sides of the Channel may be explained by the course which the North Sea tide has been shown to take by the coast of Holland; for a sweep of those waters from the Norfolk headland round by that coast would carry the section which reached the Straits of Dover, through these straits towards the north; but on what principle the Alderney head-waters take a direction to the south is not apparent, except it may be attributed to a stress of that body which issues with a sweeping motion to the south out of the Dorsetshire bay and by the Portland Head, which probably is the cause; and is in itself analogous to what is seen to happen at the other extremity of the Channel.

These dispositions have presented themselves as one of those marvellous dispensations of the Great Ruler of the earth, by which the vast ocean is ordained to be at peace and its violence tamed into subjection. They can hardly, we think, be regarded as altogether casual. Take away any one of the conditions here exhibited in the arrangement of the North Sea and Channel tides, and the whole area of this meeting of the waters would become a scene of confusion and ruin. As it is, the whole combine together in time and space in such a way as to produce a complete harmony; the two tides being in a manner dovetailed together, and so regulated as to preserve their proper path without any interference with each other. The subject is new to ourselves, and, we believe, open to much investigation. What we have here suggested must be regarded therefore as an outline only of this supposed system; and, in conclusion, we will merely shortly trace the courses of the two tides in their approach to their final goal, which for this purpose must be taken to be London. For thus it appears to be, that the Atlantic tide-wave which passed the south coast of Ireland, say Bantry Bay, at two p.m. yesterday, would be found at Harwich at 10h 30m this morning, having traversed round by the Orkneys, where it would have been at 10h 30m last night; while the tide-wave, which was at the same south point of Ireland this morning at two o'clock, would have reached Plymouth, in an eastern direction, at 3h 30m this morning; attained its point of culmination about the Channel Islands at 4h 30m a.m., and, passing Calais at 10h 6m a.m., have been at the South Foreland also at 10h 30m

this morning, and so contemporaneously with that of the Harwich high water. These two places, Harwich and the South Foreland, whose tides are, as I have said, contemporaneous, may therefore be regarded as the extreme points of the basin out of which the London tide-waters are supplied. Two hours and thirty minutes before the London high water, the tides culminate upon Harwich from the North Sea, and upon the South Foreland from the Channel. They meet in crossing the Nore, an hour and a half after the Harwich and South Foreland tides; and the tides which have been traced to these places this morning at 10h 30m, will therefore have reached their destination at London at one o'clock this day.

Friday, February 15th, 1861.

COLONEL PHILIP J. YORKE, F.R.S., in the Chair.

THE MILITARY FORCES OF THE NATIONS OF EUROPE.

By CAPTAIN MARTIN PETRIE, 14th Regt. Topographical Staff. It will be my endeavour to-day to give some account of the Military Forces belonging to the several European powers.

At the present time, we can hardly be unconscious of the immense development which the warlike resources of each nation are receiving every day, and the great and growing importance attached to the naval and military element by the governments of every state in Europe; one nation striving to rival another in the extent and the perfection of its armaments. Administrative talent was never so severely taxed to increase the personnel available for an army; and the powers of science and art are exerted in an equal proportion, to originate new implements of destruction, or to devise means of safety from their tremendous effects.

Abroad, the mighty engine of the conscription extends its resistless grasp in every direction; whilst at home, the free youth of Britain respond to their country's call-the gleaming bayonet is a welcome ornament in the quiet hamlet or the mart of industry, and one smile of acknowledgement from a monarch whose securest home lies in the hearts of her people, is deemed an ample reward for every exertion and fatigue.

While the marshalling of men is proceeding thus, fresh fortresses are rising through the length and breadth of Europe; colossal walls of stone, and even of iron, with tortuous labyrinths of ditches, spread far and wide, in the endeavour to guard each point vulnerable to a foe.

The ocean, once speckled with the white flowing canvas and tall masts of our wooden castles, in these days bears on its surface the huge smoking armadillo of iron, less picturesque, but more mischievous; and, when we come to the workshop, we find mechanical contrivance no longer limited to the crude weapons of a few years since, but creating structures whose vast proportions the Titans might envy, yet whose delicacy of finish the most expert fairy could hardly excel.

France, though professedly not arming, or placing her forces on a war footing, is straining every nerve to bring her troops to the highest state of efficiency, to have them prepared for action at a moment's notice, and "in a condition to meet all emergencies." The matériel of her army is being improved and remodelled with all the aids that science or ingenuity can suggest, and her naval arsenals resound with the echoes of ten thousand hammers, under the strokes of which not less than thirteen iron floating

batteries are gradually rising to completion; these, when launched, will form a most formidable addition to the already powerful maritime forces of the country.

Prussia, too, is endeavouring to organize her army on a more effective basis than hitherto, to improve the arms and equipments of all branches of the service, and to strengthen her frontier fortresses in every manner that is practicable.

Austria, though exhausted and shaken by the events of the last two years, is, nevertheless, making ready for a contest; the points open to attack will now be strengthened with works on the newest principles of art, while the famed Quadrilateral bristles with bayonets, and the Kaiser is preparing to confront the louring storm.

Italy tells us of a million of bayonets to be assembled in the approaching spring, to consummate the vindication of that national existence, which has so long been the aspiration of her statesmen and the theme of her poets. Mysterious cargoes of arms and warlike stores are stealing eastwards to the Principalities, with the view of effecting such a diversion in Hungary as shall compel Austria to relax her eagle grasp upon Venetia.

the Colossus of the North idle. Profiting by the experience of the late war, the Czar Alexander is endeavouring, while reducing the numbers of his unwieldy legions, to increase their efficiency by adopting all possible improvements both in the administration and the material of his forces; and, though foiled in his ambitious projects of territorial aggrandisement in the West, is advancing by gigantic strides along the coasts of the Pacific Ocean, and gradually enveloping the northern provinces of the Chinese Empire.

The

The secondary powers of Europe, also, are not indifferent. Spaniards, the Belgians, and the Dutch are "sharpening their cutlasses," as Sir Charles Napier would have said; and the Danes, still more active, are commissioning their navy, and placing their regiments upon a war footing, determined to show their opponents that now, at all events, "there is nothing rotten in the state of Denmark."

EUROPE, as it is at present politically divided, consists of fifty-two separate kingdoms and states, the largest of which is Russia, and the smallest the little republic of Andorra, situated somewhere among the snowy peaks of the Pyrenees; the military power of this last, however, can be safely regarded as of no great weight in European combinations. Of these states we may reckon five whose military and political strength entitles them to be called First-rate Powers. They are

To the five we hope soon to see a sixth added. I allude to the Kingdom of Italy, which, despite all obstacles, promises ere long to