182 CAVES AND CAVE DEPOSITS. 
So the bone-earth which was said to occur 4 feet beyond the 
entrance to the cave was really all within the original cave before 
this portion of the wall had fallen in. 
It was impossible that this could be an ancient mouth of a 
cave round which talus from the rock above had accumulated, 
and that the sea had afterwards crept over it and deposited the 
marine drift upon it, because the great angular blocks occurred 
at various levels in the clayey and sandy débris, and the drift 
was crushed in upon some of the fallen masses so as to stand 
vertically, with the included fragments arranged as in the case 
of the drift in the quarry on the other side of the valley, where 
also it has sunk into fissures and caves of the limestone. 
The pebbles stood with their longer axes vertical, and the bed 
of grey clay was even a little reversed in places. The inclina- 
tion of the beds decreased through about 4 feet of angular 
limestone and overlying sand and loam till the drift by degrees 
resumed its almost horizontal position. 
Fig. 1.—Plan of Cae Gwyn Cave. (Scale 34 feet to 1 inch.) 
Entrance to cave. 
. Break in the side of cave known as ‘‘ Upper Opening,” where the bones, 
&c., were found outside the then existing cave. 
Cutting made after discovery of the upper opening 6. 
. Débris of roof and wall of cave overlying bone-earth. 
Extension of. cave to the north along which water now drains away under 
the drift 
The arrow indicates the point of view in fig. 2. 
o8 
Sas 
