6o 
Discovery of Stone Implements in [January, 
it was seen going down to and below the river, the surface 
of which is about 40 feet below the top of the bluff. 
The irregularly stratified beds, No. 2, contain generally 
much smaller stones than No. 3. These beds, as in the 
former case, were pointed out to me by Dr. Abbott as the ones 
from which he had obtained the implements, and whilst I 
was present he discovered a rude one in the talus which ap- 
peared to have come from them, as we were too high up the 
slope for it to have come from the lower bed. 
The bed of sandy clay (No. 1 in Fig. 1) has been denuded 
from the top of the bluff, but a little way back from the 
edge it appears, and contains great boulders scattered over 
its -surface. 
From all the sections that I saw, and from the information 
given to me by Dr. Abbott, I have constructed the general 
section (Fig. 3) showing the succession of the beds. Up to 
Fig. 3.— Diagram Section below Trenton. 
River 
Delaware 
1. Sandy clay, unstratified, with a few pebbles, and with very large ar-transporte 
boulders on or immediately below the surface. 
2. Irregularly stratified sands and gravels. Stone implements. 
3. Pebble and boulder bed. Stones up to 15 inches across plentiful ; larger ones 
rare. Stones mostly rounded, with a few subangular ones; no scratched 
ones seen, 
A. Alluvium. 
C. Cretaceous marls and clays. 
the time of my visit (October, 1877) no implements had 
been found in the lower quaternary bed (No. 3), though it 
seems to me extremely likely that they will yet be discovered. 
This bed, of mostly rounded boulders and large pebbles, is 
quite unstratified. Amongst the pebbles are many flattened 
ones, similar to those from which some, if not all, the im- 
plements found in the higher beds have been made. This 
rounded boulder-bed is of great extent, and has been 
described by Prof. W. B. Rogers* as extending from the 
Delaware into Virginia. At Washington the deposit covers 
the whole plain on which the city is built, rising to a height 
of about 200 feet above the sea over the low hills around it. 
Prof. Rogers has found in it stones containing Scolithus 
linearis, a well-known fossil of the Potsdam formation, 
having its nearest outcrop on the western side of the Blue 
* “ On the Gravel and Cobble-stone Deposits of Virginia and the Middle 
States.” Pioc. Bos. Soc. Nat. Hist., 1875, vol. xviii., p. ioi. 
