SIXTH REPORT OF THE DIRECTOR I909 I9I 



stones of the Chazy beds, postglacial waters have not cut back its 

 walls to an extent that will yet allow the removal of the impris- 

 oned pebbles. The block offers still more conclusive evidence, for 

 though slight movements have enabled it to grind its own lower 

 surface and the bed on which it rests, thus allowing water to have 

 free access to its other surfaces, it has suffered but slight loss in 

 size since glacial time. We have thus an additional proof which 

 supports strongly our contention from other evidence that the pres- 

 ent lake, through simple solution, has not removed material from 

 its exposed limestone surfaces to a depth exceeding 3 millimeters. 



There is yet another aspect from which we may view this cave 

 question. Wherever the purer Chazy beds are exposed on the sur- 

 face of Valcour island their unfilled master joints or fissures will 

 be found to have suffered in varying degrees by solution and 

 chemical action at the hands of surface waters. In some places 

 these joints have been so widened along considerable portions of 

 their length as to freely admit the leg of a man. In other places 

 we may find joints whose faces seem to meet at the surface while 

 they are separated in their deeper portions. Along such joints we 

 find open circular holes in some instances small and close together 

 and in other instances so large as to freely admit one's leg. I 

 have been told that holes of this type have sometimes broken the 

 legs of cattle, and I have noticed that many of these have been 

 artificially filled or covered. 



These dissolved joint crevices extend to depths of some 20 

 meters or more (65 feet and over). In Sloop bay, where a por- 

 tion of the north wall has been quarried, these joint openings are 

 seen to widen out into chambers which plainly show the effect of 

 swiftly moving waters. Such opened joints with their inner cham- 

 bers are often accessible, to foxes and many of them have been 

 used as dens. 



We are now prepared to face a new problem. If our faith in 

 the power of solution is great enough to allow us to conclude that 

 surface drainage has accomplished all of this extensive joint open- 

 ing since these rocks emerged from the Hochelagan sea, we must 

 also conclude that during the longer periods of exposure which pre- 

 ceded the approach of the Wisconsin ice sheet joint crevices 

 would have been acted upon by similar agencies, been cut down to 

 former base levels and widened out into chambers far surpassing 

 in size those now existing in this region. These two conclusions- 

 involve the making of a third as follows : To remove every trace 



