24 On a Natural PJienomenon 



to be with difficulty broken up by a strong man working with 

 a pick-axe) must at one time have been in a fluid state, sus- 

 pended probably in a body of turbid water. 



Moreover, the sides of the rock, forming a sort of irregular 

 funnel in which the clay was contained, exhibited on one side 

 (the side which may be called concave, and which as we de- 

 scended was found to be vaulted and overhanging) indications 

 distinctly suggesting, even to an unpractised observer, the no- 

 tion of their having been formed by a rotatory action of water ; 

 and that this rotatory action had probably originated in the 

 rush of water to some great cavity below, forming a sort of 

 whirlpool. Indications different in appearance, but equally 

 bearing witness to the violent action of water, were observable 

 on the opposite, or what may be called the convex side, the 

 form of which might be described as resembling a portion of an 

 inclined cylinder, or of a cone ; striped, as it was found to be, 

 from top to bottom with deep longitudinal furrows, shewing 

 that the direct downward rush of water must have taken place 

 on this side, while on the opposite and concave side the rota- 

 tory action resulting from the contraction of the lower part of 

 the rocky funnel had left its traces in a series of horizontal 

 furrows. 



It followed, therefore, as an obvious inference, that the fun- 

 nel upon which we had entered, would be found to penetrate 

 through the whole depth of the rock. The work, therefore, 

 was continued, partly from curiosity and partly for the chance 

 of finding water, till it was brought down to the level of the 

 sea, a depth of sixty-three feet from the surface ; when all fur- 

 ther operations were stopped by the influx of water. But the 

 existence of a continued cavity filled with clay, and extending 

 in a downward direction below the surface of the water, was as- 

 certained by the facility with which iron-bars could be thrust 

 down into it, for the water was not found at first, but flowed 

 in gradually as soon as the fissures of the rock were left unob- 

 structed by the removal of the clay. 



If my report had ended here, it would hardly have been 

 worth while to trouble you with it ; but the only organized 

 substance which was discovered is a fragment of bone, which I 

 send, in the hope that some of your scientific friends may be 



