As far as Scilly Isles and the Lizard’s Point, the great tidal wave, which twice in every twenty-four hours flows in from the Atlantic, maintains pretty nearly the same level on the opposite shores; and this continues as far as Exmouth on the Devon coast, and St. Malo on that of Brittany. But when this great wave reaches the “Needles” which form the westerly point of the Isle of Wight, it divides into two very unequal portions. Of these, the southern and larger portion sweeps round the base of the island, passing Freshwater and Chale and Blackgang, and then rounding St. Catherine’s promontory and running up to Dunnose with scarcely-diminished velocity; but the northern and smaller half enters the Solent, and owing, it is supposed, to the resistance of two shores (by _friction_) to its progress, advances but slowly, and does not arrive at Southampton Water before the other has made Dunnose and is filling Sandown Bay with a _back_-stream. This causes many differences in the amount of water at almost any given moment on the two sides of the Isle of Wight, north and south; and it gives rise to many curious varieties of tides, real or apparent. In one spot near Shanklin, my attention was frequently drawn to the fact of a partial tide suddenly _flowing_, for perhaps the space of an hour, during the time of ebb. But this is not the only “water-company” here at work, nor is the above the only class of phenomena resulting from such agency. Beside the _tide-wave_ there is the Ocean-_current_, which is quite a distinct thing. This current is due to a branch of the Gulf-stream; and it flows here from west to east, and from south to north. That is to say, after leaving Newfoundland, so much of it as actually reaches Britain would run up St. George’s channel northwards, and up the English channel eastwards. And although the velocity of this current is but trifling, yet, owing to its unceasing action in one direction, its effects are remarkable. Moreover, it is not affected by the waves; whether the sea be sleeping in a calm or tossed with storms, the motion of the current is the same. The only change as yet observed is when its waters come to the surface and have their temperature lowered by a chill wind; for, this gulf-stream is itself a river of _warm water_, though its bottom and banks are of the same element _cold_.