THE PROGRESS OF SCIENCE 



IOI 







A Composite Diagrammatic Cross Section of the Hudson Gorge at the 

 Storm King Crossing, showing the method of making the vertical borings, the 

 direction of the first two inclined borings, the positions of the shafts and the extent 

 of explorations. (Adapted from drawings of the Board of Water Supply.) 



during an epoch of great continental 

 elevation. The borings in the High- 

 lands have been carried to a depth of 

 750 feet without reaching the bottom. 

 This is more than twice as great a 

 depth as has been found at any other 

 point either above or below, though 

 even at Pegg's Point and at New York 

 City it is possible that there is a nar- 

 rower gorge in the middle of the river. 



The great width and depth of this 

 gorge must have been due to glacial 

 erosion when a stream of ice was 

 forced down from the wide bay that 

 then existed north of the mountains. 

 The syphon tunnel under the Hudson 

 is only one of a number of great 

 syphons and aqueducts that must be 

 constructed between the Catskills and 

 New York City. Owing to the present 



Cathedral Gorge, a postglacial entrenchment of Esopus Creek at the Tongore 

 site. The preglacial gorge lies at the north side of the valley buried beneath 250 

 feet of drift. (Photograph by Board of Water Supply.) 



