22 Wisconsin Academy of Sciences, Arts, and Letters. 
illustrate approximately the relation of the joints worked out in 
my building-stone researches in 1880. My best examples were 
found in the central and southern sections of the state.” 
Arkansas. —Professor Branner 1 2 has been good enough to call 
the author’s attention to similar results obtained by Professor 
Newsom and himself when studying the eastern portion of the 
Boston Mountains in Arkansas, in which investigation the pe¬ 
culiarities of drainage, the parallelism of streams, the similarity 
of their elbows, and the relation of these streams to structural 
features in the adjoining regions were put upon record. The 
dominant directions of drainage are NE-SW, and NW-SE. 
With greater definiteness these directions are given as N. 60°-67° 
E., and N. 51°-65° W. The NE-SW series seems to be con¬ 
trolled by the monoclinal folds. Attention is called, however, to 
the relationship existing between these stream directions and a 
series of dislocations in the province, and it is further stated 
that ‘ ‘ there are two other systems of joints in the area here 
especially considered, one running N. and S., the other E. and 
W.” 
The Great Basin of the Western United States. —Since the 
publication of the early reports upon the geology of the Great 
Basin of the western United States it has been generally recog¬ 
nized that the dominant faults trend near the meridian. Gilbert 
has also called attention to the fact that formations rather gen¬ 
erally end abruptly on east and west lines. Spurr 1 in his gen¬ 
eral conclusions upon the origin of the basin ranges of Nevada 
and California says: 
“The faulting in general seems to be about as frequent as in 
other regions which show' the same amount of folding. The 
chief faults belong to the north-and-south and east- and-west 
systems. There are also diagonal ones running northeast and 
northwest and in each of the systems they , may have a very great 
displacement. ’ ’ 
The most important directions described by Spurr are in per- 
1 Newsom, J. F., and Branner, J. C. The Red River and Clinton 
Monoclines. Am. Geol., Vol. 20, pp. 1-13. 
2 Spurr, J. E. Origin and Structure of the Basin Ranges. Bull Geol. 
Soc. Am., Vol. 12, 1901, pp. 217-270. Pis. 20-25. 
