It is clear that the face of the precipice has been gradually receding in proportion as it yielded to the action of the waves; and that at a former period the volcanic rock extended considerably further than at present over the beds which are seen to dip beneath it. These latter consist of hard fine-grained calcareous sandstones belonging to the Lower Carboniferous formation. Their colour varies from red to white, and their prevailing dip is in a N.W. direction, with an average inclination of 12-20°. If the volcanic mass is a true intrusive rock, we should naturally expect the strata which surround it to dip _away_ in all directions, the amount of their inclination diminishing in proportion to their distance from it. We find, however, that the case is precisely the reverse: as the beds approach the base of the cliff, they dip _towards_ it from every side at perpetually increasing angles, until at the point of junction the inclination amounts in places to as much as 55 degrees. The exact amount of dip in the various positions will be seen on referring to the accompanying map. [Illustration: FIG. 1. MAP OF STRATA AT WHITBERRY POINT. Scale, 6 in. to the mile. _A._ Lava sheet. _B._ Sandstone Beds, dipping from every side towards the lava. _CC._ Line of Section along which Fig. 2 is supposed to be drawn.] We conceive that the phenomenon is to be explained by supposing the orifice through which the lava rose and overflowed the surface of the sedimentary strata to have been very much smaller in area than the extent of igneous rock at present visible; and that the pressure of the erupted mass on the soft beds beneath, aided perhaps by the abstraction of matter from below, caused them to incline towards the central point at a gradually increasing angle. The diagram, fig. 2, will serve further to illustrate this hypothesis. _A_ is the neck or orifice by which the melted matter is supposed to ascend. _C_ shews the sheet of lava after it has overspread the surface of the sandstone beds _B_, so as to cause them to assume their present inclination. The dotted lines represent the hypothetical extension of the igneous mass and sandstones previous to the denudation which they have suffered from the action of the waves. Professor Geikie, in his admirable treatise on the Geology of the county[4], adopts a view on this subject which is somewhat different from that which is suggested in this paper. He considers that the whole mass is an intrusive neck of rock with perpendicular sides; and that it once filled up an orifice through the surrounding sedimentary strata, of which it is now the only remnant. Footnote 4: _Memoirs of Geological Survey of Scotland_, sheet 33, pp. 40, 41. [Illustration: FIG. 2. VERTICAL SECTION THROUGH CC. DIAGRAM (FIG. 1). _A._ Orifice by which the lava ascended. _B._ Sandstone Beds. _B´._ Hypothetical extension of ditto. _C._ Sheet of lava spread over the sandstones _B_. _C´_. Hypothetical extension of ditto.]