There is a very curious fact noticed here with respect to the _Woodcock_. These birds generally arrive in Scilly before they are observed in any part of England; more frequently with a north-east,[44] though sometimes with a north-west wind, and are often so exhausted as to be caught in great numbers by the inhabitants, especially near the light-house, the splendour of whose light appears to attract them, and striking against its lantern they not unfrequently fall lifeless in the gallery. It is for the naturalist to consider from whence they migrate. The Climate of these islands is both milder and more equable than that of Cornwall, but this advantage is counterbalanced by the frequent occurrence of the most sudden and violent storms. By those who have kept journals it has been found that not more than six days of perfect calm occur in the course of a year, and that the wind blows from between S.W. and N.W. for more than half of that period. With respect to Geology, these islands will afford but little variety; with the exception of some beds of _Porphyry_ at Saint Mary's, and some beds of _Chlorite_, containing _Pyrites_, in the same island, they consist entirely of Granite, and are doubtless a continuation of the Devonian range, although the rock assumes an appearance less porphyritic; it contains, however, veins of red Granite. At the Lizard Point in the island of Trescow, a variety of granite occurs, in which the felspar is of a remarkably pure white, and might, we should conceive, be advantageously employed in the manufacture of Porcelain. In some chasms of this rock, and in the centre of large masses, the _Mica_ is of a silvery hue, and occurs crystallized in its primitive form. In the same island is a remarkable cavern, in the centre of which is a pool of fresh water. The porphyritic beds in Saint Mary's are interesting on account of the distinct appearance of stratification which they display, and _Mr. Majendie_ thinks that an undoubted instance of stratified granite is to be seen near the same spot. The Granite of Scilly is very liable to decomposition; whence has arisen all that fancied statuary of the Druids, of which we have spoken in another place. The Islands are undoubtedly undergoing a gradual diminution. At no great distance of time Saint Mary's will probably be divided by the sea, and a channel formed through the low land between the New-town and the south-east side of the garrison. This might perhaps be prevented by throwing down masses of granite from a neighbouring hill, so as to form a barrier against the sea. The object may be worthy of attention, as the sea in winter, with a high tide, has been known to pass over this land, and the effect of its forcing a channel there would be to divide the garrison from the rest of the island. If the Geologist proceeds to a spot behind the quay, and between the front of the garrison-hill and that island, he will be gratified by the discovery of a process the very converse of that