Lansing Pleistocene Geology. — IVinchell. 307 
therefore were two contemporary detatched quiet water bodies, 
so far as indicated by the tunnel, one about fifty or sixty feet 
north from the other. Was the material which subsequently 
covered these silted strata brought from the north or from tlie 
south? Was it borne by an influx of greater volume of water 
from the north or was it the product of a land-wash from the 
south ? 
At seventy-two feet from the entrance, where the skeleton 
was found (plate XVIII) No. 4a reappears, and over it in a 
mass of formless clay resulting probably from its disintegra- 
tion, the human remains were discovered. This overlying ma- 
terial, No. I, was from two to'three feet thick, containing not 
only debris from Carboniferous shale but also large pieces of 
limestone. How much of No. i here was contributed bv decay 
of limestone is uncertain, but it is safe tO' infer that the larger 
part was derived from No. 4a and from adjoining Carbonifer- 
ous shale in situ. No. i shows, in every sense, the characters 
of geest, chemical, microscopical and structural, and its origin 
can be assumed to be only that which is ascribed to geest, viz., 
a residuum from decayed and decaying rock. It so happens 
here that one of the forms of the parent rock was easily dis- 
integrated, and further possessed, prior to disintegration, es- 
sentially the composition of geest, and that, hence, the chemical 
transformation was less, and the product of geest was greater. 
At eighty-three feet from the entrance (station G) the 
cliaracters of No. i extend from the Carboniferous shale nearly 
to the roof of the tunnel, having a thickness of about five feet. 
The result of this special examination is, as should have 
been expected, the restriction of the geest practically to the last 
fifteen to twenty feet of the tunnel. In this geest has been 
found no drift pebbles, nor quartz sand, nor valley wash, nor 
heterogeneous mixture. It is wholly referable to the under- 
lying rock. The most of the contents of the silt layer was 
undoubtedly derived from tliis geest, as it contains so large 
a percentage of kaolin, undistinguishable from it. Had the 
lowan loess been present to supply material for this silt it 
would probably have approximated more nearly to the loess 
in its composition. 
After the deposition of the silt, by wash from the geest and 
from the Carboniferous and from the Kansan drift, the action 
