HAWORTH. | The McPherson Hquus Beds. 993 
Smoky Hill river ran south instead of north and emptied into the 
Arkansas. But it is difficult to understand why it should have 
excavated so great a channel and covered so wide a flood plain 
here and so narrow a valley west of Marquette. However, the en- 
ecroachment of the sandhills on its southern area may offer a shght 
suggestion as to the partial choking of the southern outlet causing 
more rapid deposition to the north, and thus elevating the channel 
and widening the tlood plain. 
But there are other facts which seem to detract from this ex- 
planation of the origin of these beds. If the Smoky Hill river at 
one time flowed south into the Arkansas, then one of a number of 
conditions must have obtained. 
First: The Saline could have received a short tributary from 
the southwest, occupying the position the Smoky now has through- 
out that part of its course above Salina where it flows north. The 
source of this tributary could have gradually migrated southwest- 
ward by natural processes until it captured the Smoky at the 
point of the big curve in the present river. The accumulation of 
sand above referred to along the northern side of the Arkansas 
would have assisted in this by elevating the mouth of the old 
Smoky. but unfortunately for this view no part of its course 
south of McPherson is as high as the high McPherson ridge, which 
is 1550 feet above sea level near McPherson to the north. Were 
this ridge formed by the natural filling-up process in the old valley 
of the Smoky before its capture, we should find some evidence of a 
corresponding filling further up stream in the present valley and a 
widening of the valley corresponding somewhat with the wide 
valley now occupied by the Equus beds. No such filling or widening 
of the valley is noticeable. Further, at all points above the McPher- 
son ridge the bottom of the channel must have been at least as high 
as the ridge, and a short distance away it must have been higher. 
At present one must pass upstream over thirty miles, to above 
Ellsworth, before the river channel has an elevation of 1550 feet. 
After the capture, on account of the Saline near Salina being so 
much lower than the Smoky in its hypothetical position, a rapid 
deepening of the channel would have occurred throughout a dis- 
tance of from thirty to fifty miles above Salina, and a new flood 
