F. D. Ohester—Distribution of Delaware Gravels. 198 
yet from the vertical heights at which this gravel is found the 
current must have been deep as well as swift. A glance at the 
map will show that the northern limit of the Delaware Gravels 
runs approximately parallel to the river, where the same 
crosses the northern limits of the State. This river during the 
latter part or close of the Glacial period was, as we know, a 
swollen rushing flood, having a width of about ten miles and 
an average depth of over 200 feet. It emptied into the Dela- 
ware listuary near Wilmington, and its current, urged on with 
a tremendous head, instead of bending to the south and south- 
east, as is indicated by the present flow of the river, must have 
continued in its same southwesterly course entirely across the 
State into Maryland, until it reached the head of the Chesapeake, 
where it was stopped by the high hills which rise above the 
level of the shore line. A belt of gravel thus stretched across 
the bead of the estuary by the current of the river would be 
sieesncntly spread out by the waves as a broad sheet to the 
south. 
process of construction, and extending approximately along 
the entire length of the shore line has offered most valuable 
aid, especially as the sections there are freshly cut. 
Section on Baltimore and Ohio R.R., Newark, Del. 
Feet. 
2 
. Yellow brick clay, free from gravel ---. ‘ 
Red Sand, highly argillaceous, free from gravel ---- 8 
Rock undecomposed. 
ers 
Section in Gravel Pit, Newark, Del. 
- Yellow brick clay, free from gravel ....._.-------- 3°5 
- Red micaceous sand, free from argillaceous matter 
with coarse gravel and sand in lower part ---- ---- 12 
3. White fire clay. Cretaceous. 
ne 
One mile north of Newark, on Pa, RR. 
1. Yellow brick clay. ___. Oe OP et spt 
2. Red sand, coarse, micaceous with oval quartzose 
COieN 0b Gai eee eke ee sd 
3. Alternate layers of gravel, wi 
sand, irregular bedding 
SUIURLUTS 52.5 ee 
4. Fine yellow clean sand 
