184 NEW YORK STATE MUSEUM 



where most of the Chazy beds are exposed there are but a few 

 beginnings or remnants of caves in the very beds in which they 

 should abound. The cutting back of the cliff by the process in- 

 dicated gives the cave-forming forces but little chance to outrun 

 it. On the shore represented in plate 1 the wave energy is much 

 less powerful owing to the projecting capes to the south. Here 

 outer destruction follows inner formation at a respectful distance. 

 At long intervals a fragment of the side wall of the caverns 

 some distance in . may become dislodged and plate 11 shows 

 several edges that could be easily removed. A few such have 

 been found in the debris partly filling some of these caves. How- 

 ever large a part this destructive agent may have played with 

 outside walls as we enter the caves its power is reduced with 

 the distance to which we penetrate until finally it is entirely 

 inoperative. It is widening the mouths of the caves somewhat 

 and increasing their hight in some, instances but it is doing 

 nothing to carry them deeper into the cliff. 



Evidence from preliminary excavation. The floor of Bat 

 cave is deeply covered with blocks which must have fallen in greater 

 part from the roof though doubtless there have been also many 

 contributions from the side walls. An effort was made during 

 low water of the present season to penetrate this mass 

 and find the cave floor. The first blocks removed were very 

 heavy and showed little trace of either solution or erosion. Some 

 of the unmoved blocks of this layer may be seen at the lower 

 left in plate 11. The material we removed was all carried toward 

 the front of the cave and much of it thrown completely out. 

 After getting down about a third of a meter the surfaces of the 

 blocks began to show plainly the effects of differential solution, 

 and at about a half meter this aspect became pronounced. For 

 the next half meter the blocks had to be removed from under 

 water and not a single block was found that showed the least 

 sign of any movement in the mass. As a rule the lower blocks 

 were smaller, but all possessed angular outlines and not one 

 showed a rubbed surface. Some of these lowest blocks had 

 edges so thin as to be easily broken off by the fingers, and all 

 showed differential solution to a very marked degree. One 

 specimen taken from the depth of about a meter was photo- 

 graphed, and a view of it is presented on plate 20. A study of 

 the surface and edges here shown will convince any one that 

 wave motion since the glacial period can have had no effect 



