THE AUDUBON BULLETIN 



W. W. Rathbone— Photo. 

 CAMP UNDER THE CLIFF NEAR CLARIDA SPRING 



and at a level so near that of the Ohio that back water in flood time reaches 

 from Shawneetown to Harrisburg, twenty-five miles away. The Saline 

 river and its tributaries display the same sluggishness as the lower Missis- 

 sippi. 



In the counties of Saline, Gallatin, Hardin, Pope, Massac, and John- 

 son, the variety of physical phenomena is not equaled by any equal area 

 in the State. Two or three other counties to the west are probably of as 

 much interest but their features are not so familiar to the writer. 



The southern limit of glaciation in Illinois coincides roughly with the 

 course of the Saline river. The drift is not very apparent at this limit but 

 it gives the student a thrill such as he feels when he first stands on some 

 famous battle ground, to stand where the great ice sheet made its last ad- 

 vance and to say : "This is historic ground." 



Reference to the geological map of Illinois reveals several fault lines, 

 of which the Gold Hill axis is the most prominent in the region under dis- 

 cussion. A slip of several hundred feet along this axis in southeastern 

 Saline county, for a distance of several miles, has left a vertical cliff fac- 

 ing the northwest, known as Eagle Cliff. Its magnitude is indicated by 

 the fact that, although an extensive talus slope lies at its base and the top 

 extends to but a small fraction of its height before erosion began, it can 

 be seen for more than twenty miles from the northwest. The slope is 

 gradual from the top toward the southeast. It is a typical "block moun- 

 tain." A limestone cave, extending in each of two directions not to ex- 

 ceed a quarter of a mile from its mouth, near the top of the cliff, is ex- 

 plored without danger that the wanderer will become lost. He needs but 

 to remember that the strata in this "mountain" all slope down to the south- 

 east. Much unfounded tradition still lingers in the minds of many of the 

 native population concerning the nature and extent of this cave. Many 

 believe that this cavern is continuous with the one at Cave-in- Rock some 

 twenty-five miles away. This is impossible from geological considera- 

 tions. I and others, some co-operating and some working independently, 



