INTRODUCTION. 



west and south converges and flows southeastward through a nar- 

 row valley as the Chemung river, emptying into the Susquehanna 

 a short distance south of the New York state line. In this part 

 the country again becomes elevated, especially in the south, where 

 the crests rise to heights of two thousand feet or more above tide. 

 After being joined by the Chemung, the Susquehanna enters a 

 deep and narrow canyon, through which it flows for many miles 

 in a tortuous course, and so passes beyond our limits. 



GEOLOGY. 



Little attention seems to have' been paid to the geology of this 

 region* perhaps from the fact that it is considered rather dull. 

 The rocks consist entirely of the Catskill and Chemung forma- 

 tions. Of these the Catskill group is composed of compact sand- 

 stones which cap the higher elevations, being most noticeable in 

 the south, east and southwest, and often wanting in the northern 

 and central portions. The valleys of most of our rivers and 

 streams are cut into the softer shales of the Chemung group, which 

 underlie the whole region ; in fact the outcrop of these rocks along 

 the Chehfung river has given the name to the series. Owing to 

 this softness of the bed rock, our region presents few clififs and 

 bold precipices, the valleys for the most part sloping gently to the 

 surrounding hills. The flora, therefore, lacks many of the char- 

 acteristic plants of a more broken country. The greatest ex- 

 posure of rock is seen in the east and southwest, where the Cats- 

 kill series predominates. In other parts, the ravines cut by the 

 streams in their descent give us sections of the Chemung shales 

 to the depth of a hundred feet or more. 



During the glacial period this district was deeply covered by 

 the ice-sheet. ICvidences of this are to be seen in the drift that 

 everywhere strews the surface, and which in the larger valleys 

 lies heaped in ridges, terraces and mounds composed of angular 

 and rounded fragments of shale, limestone, sandstone and quartz- 

 ite. In its course through southern New York, the Susquehanna 

 flows over a buried valley filled with drift to unknown depths. 

 Large amounts of clay, also of glacial origin, occur in various 

 places. 



The soil of the river bottoms is mainly alluvial ; on the slopes 

 and uj)lands it is a clay or gravelly loam derived from the glacial 

 debris, or frequently from the decomposition of the underlying 



