ARTESIAN WELL SECTIONS AT ITHACA, N. Y 



n 



is, from 70 to 200 feet, it is a fine-grained clay, at all depths 

 lower than lOO feet containing small angular pebbles, in some 

 cases scratched. These stones increase in number and size 

 toward the bottom, and the proportion of sand increases to such 

 an extent that below the depth of 135 feet the well- driller calls 

 it a sandy clay. But 



1: 





down to the 200-foot 

 level the stratum is 

 unquestionably clay. 

 Owing to the 

 indefiniteness of the 

 nomenclature used 

 by well-drillers, and ZLTIlI-T 

 the failure in many 

 cases, to preserve 

 samples it is not 

 always easy to state 

 exactly where the 

 bottom of the clay 

 series is. Using" the Y\g. 2. — Profile of the hill slope on the western side 



, ^ . J , • of the Cayuffa Valley at Ithaca just west of the artesian 



best ludgment possi- ,, . L. ., ■ .• j j ^ ^u 



-' ° ^ well sites. This profile is continued down to the points 



Die, i place tne base where rock was reached in the artesian wells. (Horizon- 

 of the clay series in tal scale, i mile to the inch; vertical scale, 1,000 feet 



the thirteen wells as '° ^^'^ '^'"''^■^ 

 follows: 220,210-30, 



262-76, 238-78, 230, 225-76, 200, 214-80, 202-22, 24^-70, 

 240, 242-46, 234-70. The well which gives the 200-foot level 

 for the bottom of the clay is the one from which most samples 

 were obtained, and for that point may be accepted as correct. 

 It is, however, the farthest south of all the wells, and it does not 

 follow that the bottom at that point is the same level as the 

 bottom at other points. On the contrary, all the evidence seems 

 to indicate that the base of the clay series is decidedly irregular. 

 As the base of the clay series is approached, and after it is 

 certainly passed, a series of beds of marked irregularity is 

 encountered. They are prevailingly coarse-textured, and in 

 every well include some sand or gravel. In many of the wells 



