107 JOURNAL OF THE 
currence of diabase dikes in the Jura-trias sandstone 
crossing the channel of the stream. 
ON THE YADKIN AND CATAWBA RIVERS. 
The conditions favoring the development of waterpow- 
ers in granitic and gneissic areas have been described 
very briefly above, and the cascades and shoals and 
rapids on the Yadkin and Catawba, as well as on the 
tributaries of the Broad, will generally be found to have 
their origin in local changes in the character of the rock, 
in one or another of the ways there suggested. All of 
the conditions there described are to be found illustrated 
at intervals in this region. 
As will be seen the shoals on the upper Yadkin, 
which lie within the area now under consideration, are 
less numerous than those on the same stream in its course 
across the belt of slate and schist already described. And 
inasmuch as the changes in the character of the rock in 
the region of the upper Yadkin are for the most part not 
radical, the amount of the fall at each of the shoals is 
less great than in the slate belt. This fact, together 
with the diminishing volume of water as we ascend the 
stream, render the powers on the upper portions of this 
stream less important. 
The Catawba river, which, like the Yadkin, rises 
along the crest and eastern slope of the Blue Ridge, 
flows nearly a hundred miles in a northeasterly course 
and then turns southward. Its course in North Carolina 
lies entirely within the gneissic and granitic area. From 
Morganton eastward fora distanca of nearly 40 miles the 
river either parallels the general strike of the rocks or 
crosses it obliquely. The changes in the character of 
these rocks are not numerous, and the number of shoals 
correspondingly small, though several of them are of 
considerable magnitude. ‘The river then runs in a south- 
