42 



position of the remains indicate shallow water with a dis- 

 tinct current, though with probably a small amount of 

 mechanical sediment. 



Several small thrust or reversed faults may be noted in 

 this section. They have mostly affected the trilobite beds, 

 and the calcareous bed six feet above them. The vertical 

 displacement is never more than a few inches, yet the 

 occurrence of these faults in connection with that of Section 

 5, and another one on the lake shore, present a problem of 

 extreme interest. 



GENERAL REMARKS. 



At several places in the gorge, gas bubbles up through 

 fissures in the rock. Near the upper end of Section 5, above 

 the falls, bubbles of gas constantly escape from the water. 

 In the gorge above the railroad bridges, opposite the 

 village of North Evans, gas escapes from a fissure in 

 the rock in such quantity as to give a steady flame when 

 lighted. The occurrence of such gas springs has led to the 

 sinking of a well in the gorge near the head of Section 6. 

 The supply of gas thus received has diminished but little 

 during a number of years of steady flow. 



The origin of the gas is probably to be sought for in the 

 bituminous shales, some of the springs undoubtedly deriving 

 their supply from the deeply-buried black Marcellus beds. 

 The gas well, however, draws its main supply from Silurian 

 strata, which are tapped several hundred feet below the 

 surface. 



The Mouth of the Stream. An interesting problem in the 

 shifting of the mouth of a stream by current and wave 

 action is presented by Eighteen Mile Creek. Running out 

 from the left bank is a long sand bar, which effectually 

 closes the mouth of the gorge, and compels the stream to 

 find its outlet at another point. The bar formerly extended 



