ARTESIAN WELL SECTLONS AT LTHACA, N. Y 



71 



least 430 feet below the delta at Ithaca, or about 25 feet below 



sea- level. Since soundings in Lake Cayuga reveal a depth of 



435 feet in the deepest point, in which, of course, there is at least 



some filling, the borings at Ithaca 



do not add to the known depth of 



the valley. It is not. to be inferred, 



however, that the deepest boring at 



Ithaca, although near the middle of 



the valley, really represents the 



deepest part of the valley in this 



region.^ The discovery of rock in 



these wells shows that the general 



slope of the lower valley walls is 



continued down with practically no 



change (Fig. 2), at least to the 



depth reached in the artesian wells 



(Fig. I, C and G). 



DESCRIPTION OF THE WELL SECTIONS. 



Both in the deeper artesian wells 

 and in shallow ones in the city of 

 Ithaca the upper layers are found to 

 be a fine-grained, massive clay. In 

 two cases it is reported as sandy. 

 This clay layer is absent, or at least 

 not continuous, near the eastern wall 

 of the valley where alluvial fans have 

 been built opposite the stream 

 mouths. The depth of the clay 

 stratum varies from approximately 

 40 to 60 feet. Fragments of mol- 

 lusca and plant fragments, including 

 pieces of reeds and wood, were 

 found in several of the samples from 

 this clay layer; and in two cases logs were encountered, one 

 at 38-39 feet, another at 33 feet. 



' It is noteworthy, in this connection, that a well near the center of the Seneca 

 Valley at Watkins had not reached the bottom of the drift deposits at a depth of 

 1,080 feet. 



Fig. I. — Section of the "Ith- 

 aca Sheet" (U. S. Geological Sur- 

 vey) to show the location of the 

 artesian wells. J, B, salt wells, 

 rock at 430 and 401 feet respect- 

 ively; C, Strang Well, No. i, 286 

 feet, struck rock at 260 feet; D, 

 Millard Well, No. 2, 259 feet; E, 

 Old Clinton St. Well, 280 feet; 

 F, South Well, 232 feet ; G, Strang 

 Well, No. 2, 352 feet, struck rock 

 at 342 feet ; H, Trapp Well, 332 

 feet; /, Holmes Well, 291 feet; /, 

 Millard Well, No. i, 303 feet; K, 

 several wells, close together, as 

 follows: Illston Well, 286 feet; 

 Strang Well, No. 3, 280 feet; 

 Strang Well, No. 4,279.9 feet; 

 Strang Well, No. 5, 276 feet ; and 

 Strang Well, No. 6, 295 feet; Z, 

 Millard Well, No. 3, 303 feet. 



