in the Cayuga Lake Region. 



235 



north of Willow Cr., the first on the south limb of the anti- 

 cline, the second on the north limb, the dip on both being 

 slio'htlv less than 1°. 



Fig. 4. — Intersecting faults in the Encrinal layer between Crowbar and 

 "Willow Cr. west shore Cayuga Lake. Xotiee the change in angle of dip as 

 the faults enter the underlying shale, as well as the wedge-shaped block lifted 

 up by the horizontal pressure. 



Fig. 4 will bear repetition here as giving, from nature, 

 an example of faulting strikingly similar to the results of 

 one of Daubree's famous experiments, as shown in fig. 5. 2 

 The block subjected to direct pressure from both ends 

 was a mixture of plaster, beeswax and resin, made to 

 approach natural conditions as nearly as possible and in 

 which were developed fractures formed at angles of about 

 45° to the direction of compression. The wedge shape 

 of the fault block produced in the Encrinal, though of 

 such small size as to almost forbid comparison, seems to 

 illustrate a movement similar to that suggested by 

 Mr. R. T. Chamberlin in his article on ' ' The Appalachian 

 Folds of Central Pennsylvania." 3 



2 Fig. 5 is a photograph of plate II, fig. 3 accompanying a discussion on 

 p. 316, taken from " Etudes synthetiques de geologie experimentale, vol. I, 

 by A. Daubree. 



3 Chamberlin, E. T., Jour. Geol., vol. 18, Xo. 3, 1910 (especiallv pp. 246- 

 259). 



