508 Dr. E. F, 8charff, etc. — Exploration of Kesh Caves. 



the gallery to the right, deep down in this stratum ; while charcoal 

 was found lower down in the same deposit and in the same bench, 

 each bench measuring two feet wide. 



In several parts of the cave the upper stratum contained bones 

 of brown bear. These were found near the lower horizon of the 

 deposit, so that in some cases they may have been lying on 

 the surface of the clay which formed the second stratum where 

 the deposition of the upper one commenced. In one case a bone 

 of a bear was partly embedded in the upper stratum and partly in 

 the clay. 



Bones of field mice were numerous, as well as those of frog. 



The second stratum of clay, which also extended throughout the 

 galleries of the Plunkett Cave, was brown, inclining to ochreous, 

 more or less sandy, and contained numerous fragments of limestone 

 and chert. Worn rounded pebbles were scarce in the clay, and 

 occurred chiefly in or near the Water Gallery. 



The quartz sand in this yellowish clay seems to be truly detrital 

 and of external origin ; it sometimes largely predominates over the 

 clayey particles. The clay itself, however, probably arises from 

 the decay of certain layers of the limestone, since it contains, and 

 at times abundantly, the typical bipyramidal crystals of quartz. Its 

 non-calcareous nature shows that it was deposited when solution 

 was fairly active, while the upper tufaceous deposits indicate con- 

 ditions favourable to stalagmitic growth. 



The presence of occasional worn pebbles of red sandstone in the 

 interior of the caves might be explained on the supposition that 

 the pebbles had been washed down pot-holes and crevices from 

 tlie hill above. The gravelly deposit at the mouth of the Plunkett 

 Cave could not, however, be thus explained. It is too thick and 

 too limited in area, and some of its contained boulders are too large 

 to have been thus introduced, and there seems no escape from the 

 conclusion that the gravel has been washed to the mouth of the cave 

 from without. 



Some of the larger limestone boulders, especially those towards 

 the top of the gravel, were undoubtedly glaciated (not only scratched, 

 but exhibiting also the characteristic shape of glaciated blocks), and 

 did not seem to have been worn or washed much since this glaciation. 



There is not enough drift on the mountain above to explain the 

 presence of the gravel as a down-wash, even if the contour of 

 the hill were such as to render a down-wash of this kind possible, 

 which is not the case. The plain of drift, with its characteristic 

 original moundy topography, lies considerably below the mouths 

 of the caves, with a steep talus slope now separating them, and 

 it is highly improbable that there has ever been a plateau of drift 

 material so high as the mouths of the caves at any time since the 

 disappearance of the ice. There seems, therefore, to be no other 

 explanation possible for the gravel deposit than that it has been 

 washed into the mouth of the cave at a time when the ice was at 

 least as high as the escarpment into which the caves are cut, and 

 that the mouth of the Plunkett Cave was already an open passage 

 at that period. 



