GENERAL OBSERVATIONS ON THE STRATA.

201

Shanklin, Luccombe, Dunnose, and Blackgang; and may beeasily connected with the corresponding stratum in the middlerange, by tracing it from Shanklin to the Culver on the east, andfrom Blackgang to Compton on the west.

This deficiency in the chalk and green sand, therefore, is aphenomenon similar to those which have obtained from moderngeologists the title of denudations ; and may have been occasionedby the same causes.

In connecting together, and, as it were, restoring (to use thelanguage of the antiquary) this series of strata, which, thoughnow in ruins, was probably much more entire in some formercondition of the earth, a singular conclusion presents itself to theimagination, and which would seem to force itself upon our con-viction, with nearly the same certainty which we feel in puttingtogether the fragments of an ancient temple.

The conclusion to which I allude is, that the chalk of themiddle range, together with the clay of Alum bay and the inferiorstrata, once formed a sort of arch, or vault, by which it joined tothe horizontal strata of the hills of St. Catherine and Shanklin ;and that the present abrupt ending of the vertical and highlyinclined strata, is owing to the action of the same denudatingcauses which have swept away such large portions of the earthin other places.

In the section of the Isle of Wight, from north to sou th (Fig. 1,PI. L.) the dotted lines represent this supposed original structure.On examining the several sections of the strata at right anglesto their direction, as seen at the Culver and the Needles, one ofthe most remarkable circumstances is the variety in the anglesof the dip of the several beds, the whole assuming a fan-like

i) d