compose them, are numerous narrow and a few wide channels; but, as will be seen by reference to the map at the end of the volume, and the annexed diagram, a large proportion of the sea between Jersey and Alderney and the whole of that between Jersey and France, is less than twenty fathoms deep.

SECTION ACROSS THE CHANNEL FROM PORTLAND TO ST. MALO, Marking the relative position of the principal islands and rock-groups.

The sea-bottom around the Channel Islands, could we see it denuded of water, would present a singularly broken and jagged appearance. Pinnacles of granitic and porphyritic rock would be seen to rise out of large rounded masses of similar rock. Banks of sand, some of them extremely steep, would occupy intervals between the groups of pinnacles and the more important hummocks of hard, naked rock. A few comparatively deep valleys would mark the navigable passages, and a considerable degree of regularity would be observable in the width and direction of some of these. But, on the whole, the result of an elevation of thirty fathoms would be, to give a very large and well-defined tract, enclosing all the islands and rocks. This land would not be unlike the western part of Brittany, the valleys being already provided with abundance of sandy soil, the hills jagged and abrupt, and the coast terminated with a cliff going down at once into water of considerable depth.

When Jersey, Guernsey, Alderney, and Sark, are quoted as the Channel Islands, the expression must then be understood with

PHYSICAL FEATURES.

some reserve. No doubt these are the principal inhabited tracts of land, stated in order of magnitude and population; but the smaller inhabited islands,-the numerous large rocks and ledges, above and under water,—the sand-banks, from which fishes are taken, and on which ships are often stranded,—and the smaller islets and rocks, with their rocky coves and inlets, important for shelter, or requiring to be known that they may be avoided-are also of very considerable interest.

Few parts of the world present, in so small a space, so much variety as is the case with this archipelago; and few groups of islands are so remarkable for their great political and historical interest, combined with singular natural beauty. Constructed for the most part of hard crystalline rock, decomposing or weathering by the constant action of the sea and weather; exposed to the incessant dash of the waves coming in from the Atlantic, which are thrown back by the coast of the Cotentin, only to meet a fresh arrival of others, all bound on the errand of destruction;-the islands have been for countless ages beaten about, penetrated, rounded, broken and carried away,-leaving now only a fret-work of those hardest barriers that have still resisted the attack, and are enabled to present a bold and serried front against their relentless enemy.

It is very essential to a right understanding of the scenery of these islands, that their physical and geological features, and the changes they have undergone to bring them into their present state, should be appreciated. They were originally connected together, and formed part of French land. The separation being once made at various localities, the softer and more easily weathered rocks would soon be swept away by the sea, while the tougher and harder materials would offer much longer and more successful resistance.

Intersected in every direction by veins and crevices, some of the veins being filled with rock yet tougher than the granite of the mass, and some with soft minerals and clay, the result has

been the production of the islands and rocks as we see them. It is inevitable that in this contest, the land above water, that between wind and water, and that permanently below water, must have been differently though always greatly affected.

Bearing in mind these few observations, it will not be surprising that Guernsey, the outlying island, should now present a bare mass of the toughest syenite, with a coast affording the grandest and boldest scenery; while Jersey, although a much larger tract of land, more within the gulf, is softer and rounder, with larger and tamer bays, and a less severe style of beauty. Sark, somewhat the loftiest of the islands, is also the most weather-worn, and is being gradually torn to shreds. Alderney is a rounded mass: the Casquets are jagged pinnacles. The Chaussey islands are like the debris of a worn-out series of quarries. Each group has its own characteristic, and each is a resisting centre, on which the waves have long beaten, but still have only partially done their work. But there is little real difference. The granites or syenites of Guernsey and of the Chaussey islands present differences of detail, but not more so than we often find in granites from adjacent quarries. Each decomposes into a similar soil, and the practical difference between them amounts to little more than a non-agreement as to their rates of decomposition.

Islands placed as these are must be subject to certain inconveniences, inseparable from those spots whose approach involves the crossing of troubled water. There is no way of escaping from this annoyance, except by the use of vessels so large, that they could neither navigate the narrow channels, or enter the small harbours with convenience.

The course of the tidal wave through the waters that surround the Channel Islands, may be thus stated. The great wave coming in from the Atlantic, advances from the south-west, and is turned to the east. A part of it passes on to the north-east, north of the islands; but a part enters among them by various

COURSE OF THE TIDAL WAVE.

channels, and being first lifted by shoal water, and then thrown back by the coast of Normandy, it is both detained in its course, and is deflected to the north. At Mont St. Michel, the magnitude of the wave is at its maximum. Owing to the vast extent of the shallow water, and the narrowness of the deeper passages throughout the great bay enclosing the islands, the wave remains extremely large, amounting in Jersey to nearly forty feet, in Guernsey to almost thirty,* and in Alderney to about twenty feet at high spring tides; the difference between high water at spring and neap tides, being seventeen feet at the Minquiers and Jersey, eleven at Guernsey, and seven at Alderney, though sometimes very much greater on the occasion of great spring tides or equinoctial tides.

High water takes place at Jersey nearly half an hour before it reaches Guernsey, and three quarters of an hour before Alderney. The velocity of the tidal current, where not increased by narrow passages, is from two and a-half to three miles per hour.

Although the course of the tidal wave may thus be traced, the current by no means follows the same law. In this respect the complication is so great, that it would be quite impossible to describe it in detail in this place; but in a general way it may be stated, that the stream does not flow northwards with the advancing tide wave in the open channels, till the wave has been flowing three hours, and that when it has turned it continues in that direction not only till the flood has turned, but till the retiring wave has receded half its course. In other words, the stream flows from half flood to half ebb, and ebbs from half ebb to half flood. While, however, this is the case in certain channels, the direction of the stream is not only different,

The estimate of the tide at Guernsey, according to the careful observations made at the pier under the superintendence of Lieut. Richards, now conducting the survey of the Channel Islands, is as follows: mean time of high water at full moon, 6h. 46m., Greenwich time; mean range of spring tide, 25ft. 9in.; mean range of neap tides, 18ft. 9in.

but often diametrically opposite, at no great distance, but somewhat nearer shore.*

No wonder, then, that the rocks are jagged; no wonder the sand-banks are numerous and shifting; no wonder the ship heaves, and tosses, and groans, while forcing its way through these angry and powerful bodies of moving water. Rather is it wonderful that in all the islands the climate is so equable, and the weather generally so pleasant; that so little rain falls, so few fogs obscure the air, and so much comfort can be obtained at all seasons.

Owing to their geographical position, these islands are rich in certain departments of natural history. They are surrounded by shallow water, rocks, and sands, at a temperature very favourable for animal life. The water is always well aerated, there is abundant vegetation, and plenty of shelter in little caves and nooks. In this respect few parts of the coast of Europe, or its adjacent islands, are more rich. Zoophytes of almost all kinds, crustaceans, molluscs, and sponges, may be studied to perfection in natural rocky basins and caverns, and may be easily removed for study; while the sea-weeds and lichens are equally abundant, and equally available for natural-history investigation.

Owing to the climate, the vegetable productions of the land are equally remarkable. Having a more equable temperature than almost any part of the western shores of Europe, but not a larger rain-fall, there is every facility for cultivating whole classes of plants, elsewhere difficult to keep alive; and, though there is little intense heat in summer, still the absence of cold in winter is sufficiently marked to admit of the orange-tree bearing fruit, while the camellia is loaded with flowers in sheltered gardens, from December to March.

* Between Guernsey and the Casquets the current sets from every point of the compass, during each advance and recession of the tidal wave. Hence, the navigation is exceedingly difficult and dangerous in foggy weather, ships being sometimes drifted for miles out of their course.