in is thought to have been built up of
unconsolidated sands, clays, and gravels, the debris of the Jurassic
mountains. Inland the material consisted of river-made or land
deposits; outwardly it merged into coastal plain deposits. When the
plain was uplifted, these loose gravels were swept away. In New York,
Pennsylvania, and New Jersey, however, portions of the Cretaceous
deposits are still to be found. Such deposits are present, also, on
the north shore of Long Island, and a well drilled at Barren Island on
the south shore revealed not less than 500 feet of Cretaceous
strata.[3] The existence of such thick deposits within 30 miles of the
Connecticut shore and certain peculiarities in the drainage have led
to the inference that the Cretaceous cover extended over the southern
part of Connecticut.

[Footnote 1: The streams and other topographic features of the Danbury
region are shown in detail on the Danbury and the New Milford
sheets of the United States Topographic Atlas. These sheets may be
obtained from the Director of the United States Geological Survey,
Washington, D. C.]

[Footnote 2: It was probably not less than 30 miles, for that is the
distance from the mouth of Still River, where the Housatonic enters
a gorge in the crystallines, to the sea. Fifty-five miles is the
distance to the sea from the probable old head of Housatonic River
on Wassaic Creek, near Amenia, New York.]

[Footnote 3: Veatch, A. C., Slichter, C. S., Bowman, Isaiah, Crosby,
W. O., and Horton. R. E., Underground water resources of Long
Island: U. S. G. S., PP. 44, p. 188 and fig. 24, 1906.]

A general uplift of the region brought this period of deposition to a
close. As the peneplain, probably with a mantle of Cretaceous
deposits, was raised to its present elevation, the larger streams kept
pace with the uplift by incising their valleys. The position of the
smaller streams, however, was greatly modified in the development of
the new drainage system stimulated by the uplift. The modern drainage
system may be assumed to have been at first consequent, that is,
dependent for its direction on the slope of the uplifted plain, but it
was not long before the effect of geologic structure began to make
itself felt. In the time when all the region was near baselevel, the
harder rocks had no advantage over the softer ones, and streams
wandered where they pleased. But after uplift, the streams began to
cut into the pl