THE MINERAL SPRINGS OF SARATOGA I3 



been traced by Gushing and Ruedemann to the north across the 

 sheet as their map will show. To the south its exact course is 

 obscured by the glacial drift and sands, but it seems to make a west- 

 ward swerve at Congress street and Broadway and turn along Oak 

 street after which it may turn south again, but its exact course is 

 hidden by the drift. 



The fault as it appears west of the springs along Spring avenue 

 is not one of great displacement. The Little Falls (Beekmantown) 

 dolomite forms the clift" to the westward and possesses the char- 

 acters of the upper portion of this particular stratum. As it is 

 followed northward beyond the Maple avenue quarries the Amster- 

 dam (Trenton) limestone still remains on top of it, proving that the 

 top of the escarpment is near the upper limit of the dolomite. 



At the foot of the escarpment and in the rear of the Star spring 

 bottling works. Gushing and Ruedeman discovered a block of 

 Amsterdam (Trenton) at the surface on the downthrown side. This 

 fixes within fairly close limits the amount of the displacement at 

 this point. If the cliff is about 30 feet and the thickness of the 

 Amsterdam is 50 feet and some of the Amsterdam still remains 

 beneath the surface on the east side, and if its bottom can not have 

 been far above the top of the escarpment on the uplift side, we 

 have 80 feet as an extreme possibility and 50 feet as a not improbable 

 amount. 



The displacement may be greater at other places along the fault 

 line, but for so continuous a break it is impressive to find the throw 

 so small. The Amsterdam limestone is soon succeeded by the slates 

 to the eastward. 



The most striking feature of the fault lies in the fact that no 

 mineral spring has been discovered to the west of it, and where it 

 can be sharply located no spring is known very far to the east of it. 

 The Strong well is approximately iioo feet from it; the Excelsior 

 or Ten springs about 3000 feet. The wells of the Natural Garbonic 

 Gas Go. and of the Lincoln Gompany are some similar distance if 

 we give, as seems necessary, credit to the westward swerve along 

 Oak street. The course of the fault being obscured by the drift, 

 we do not know what its relations to the springs farther south may 

 be. To the north the fault splits into two; the main one following 

 the escarpment of the ancient crystalline rocks and a branch striking 

 northeast toward the Gurn spring. This spring emerges a short 

 distance from the branch fault. 



