GENERAL OBSERVATIONS ON THE STRATA.

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The consequences derived from this reasoning appear to behighly curious and important. J have mentioned the calcareousrocks which I observed in various parts, as at Bembridge,Gurnet, and Totland bay; the stone procured from these placeshas been much employed for building. It is of singular cha-racter; it has much the appearance of some sorts of tufa, and thenumerous fossil shells which it encloses, resemble strongly someof our freshwater shells.

It is well known, that in no part of England have extensivelimestone strata yet been found over the chalk; but in France ,on the contrary, there are calcareous rocks of still later formation.Can these of the Isle of Wight be analogous to the French superior strata? Is the stone of Gurnet and Totland, the Cnlcaired'eau douce, described by Cuvier and Brongniart , as existing inthe basin of Paris ? 'Phis would be an interesting enquiry. Itappears probable that a chalk basin has existed at the Isle ofWight, similar to that of Paris ; and that they have been bothfilled with horizontal depositions, some of which are calcareous.That these are contemporaneous, and analogous, is therefore atleast extremely probable.

Having now ascertained, not only the position, but the geo-gnostic place of the several strata of the island, it may beinteresting to contemplate, and to endeavour to trace, the won-derful revolutions that have taken place in this portion of theglobe ; the causes of which are, at present, and perhaps ever willremain, impenetrably mysterious, although the effects are writtenin characters sufficiently legible.

It is true, that the fabric, whose ruins we have been contem-plating, is of a nature too vast to be completely conceived as a