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GORE CLIFF.

Gore cliff, above Knowles, is a continuation of the same sec-tion as the Undercliff; but it is much higher, consisting of thewhole thickness of the stratum, with a small portion of the whitemarl above, and the dark grey or blue marl below it. A generalview of the nature of this bed is accordingly better seen here thanin any other part of the island ; but it cannot be so minutelyexamined, as access to the various parts is more difficult.

The effects of the great slip of 1799 are still visible. Thisappears not to have been accompanied with a fall of the cliff, butconsisted merely in a sliding towards the sea of the whole of theconfused mass of rocks and soil which lay at the bottom; aneffect, in all probability, owing to the same general cause whichI have already mentioned; viz. the action of the land springsupon the blue marl, which appears to have existed here in greatquantity.

About six or seven years ago, however, a considerable mass ofthe high cliff fell down ; and the large springs of water, whichstill continue to flow from under this part, together with thenature of the substance which they have exposed to view underthe sandstone, distinctly mark the cause of the failure; and theywill in all probability again give rise to a similar accident.

I found it was in contemplation to form a road over these ruins,to the mineral spring, lately discovered near Blackgang, andwhich has been analyzed by Dr. Marcet; but the instability ofthe soil will require that this should be executed with caution.*Wherever this blue marl exists, the ground is very unsafe, asseems evident from a variety of considerable failures, which havelately taken place in various parts of the Undercliff, of which this

* I have since been informed that this plan has been put in execution.