Jfeet/nif of the American Associufion.- — U/)hani. 287 
miles in central Kansas, and 60 miles in southern Kansas. The deposit 
increases in thickness southward, from eight feet in northern Kansas, 
and from 14 feet in the central part, to 25 feet in southern Kansas, and 
farther south it is even thicker. The gypsum of northern Kansas if* 
1,250 feet above sea level: of the central portion, 1,300 feet; and of the 
southern jmrt. 1,700 feet. The dip is in general south and a little 
east. 
The gyijsum occurs in three well marked areas, the northern Kansas 
or Blue Rapids area, the central or Gypsum City area, and the southr 
ern or Medicine Lodge area. The age of the northern deposit is Per- 
mian, referable to the Neosho division of Prosser. Its origin is due to 
the evaporation of an old gulf, which did not evaporate sufficiently for 
the deposition of salt. 
In the central area there are two well marked layers of gypsum, the 
lower a gulf deposit, while the upper occurs in basins of eight to twenty 
acres each, having more the character of lake deposits. Ilere the gyp- 
sum rock belongs to the Marion division of the Permjan of Prosser. 
This central area has also deposits of gypseous clay, of very consider, 
able economic importance, which are clearly secondary and of recent 
formation, being due to the precipitation from gypseoiTS springs apd the 
wash from adjacent hillsides. 
The southern or Medicine Lodge area of gypsum belongs to the Red 
beds, and was an evaporating gulf of shallow depth. 
S8. Geomorpldc Notes on. Noricay. J. W. Spencek. An account of 
the probable Tertiary and Quaternary epeirogenic movements and re- 
sulting land sculpture of Norway by subaerial erosion, based on the 
author's reconnoissances of that country during the past summer and 
in a former visit there, several years ago. 
39. The Slopes of the Drowned AuttUean Valleys. 3. W. Spencer, 
These slopes are shown to be no greater than those of the land valleys : 
and, indeed, their gradients are often found, when exactly determined, 
to be less than in the upward continuations of the same valleys (jn the 
land. 
40. Notes on Konsan Drift in Pennsylvania. E. H. Wh-liams. The 
border of the attenuated Kansan drift has now been examined. from the 
Delaware river to Butler county, near the western line of the state. It 
is found that the rock erosion was nearly all accomplished before the 
farthest extension of the ice-sheet, and that the glacial motion was very 
slack toward the extreme V)order. There is a marked difference betweert 
the drift on the border east of Salamanca, N. Y., where the sharp turn 
is made, and west of that point. Evidently this angle indicates .where 
two hjbes from different directions and with different kind.s of drift met 
and contended. The western lobe crossed to the cast .side of the Alle 
gheny river down as far as Emlenton, a little above Parker's Landing, 
thus accounting for the high level gravels as far down as that point.: 
These gravels are thought to have been quite generally brought in by 
glacial affluents from the west; and this may likewise be the origin of 
much material farther down the valley, which needs io be more fully, 
stvidied. 
