DARTON.] VIRGINIA. 181 
Gloucester may have reached the Potomac beds, and even penetrated 
them for some distance, without finding water, but as this boring 
missed the higher waters that probably underlie Gloucester, it can not 
be regarded as a decisive test lor any of the waters. 
PAMUNKEY. 
The coarse gravel and sand at the base of this formation appears to 
extend far to the east, and it is a water bearer throughout its extent. 
It was reached by the deep well at Naylors Wharf at a depth of 386 feet, 
where sands with rock layers yielded a large flow of water which rose 
to 45 feet above tide level. At Chapel Point, Md., at 237 feet, in the 
several deeper wells at Colonial Beach, at Lester Manor at a depth of 
200 feet, and at White House at depths from 180 to 230 feet, it furnishes 
a large supply of fine water under considerable pressure. These wells 
indicate a wide extent of the waters in a region which probably com- 
prises the western half of the area indicated by a distinctive pattern 
for Chesapeake and Pamunkey waters on the map, PI. XV. This hori- 
zon is about 250 feet below the Chesapeake water. The meager supply 
of water in the Clay Bank well and the failure of the deeper borings 
at Williamsburg and Gloucester probably indicate the limits of the 
horizon as a water bearer to the eastward. It may extend under 
all of the region south of the James Eiver, but none of the wells appear 
to have been bored sufficiently deep to reach it, and higher waters are 
utilized. The experience of the unsuccessful boring to a depth of 386 
feet at Dendron is not conclusive, for it probably did not reach the 
horizon, and if it did, may not have properly tested it; still, it is in line 
with the experience at Williamsburg and Gloucester. The latter criti- 
cism applies also to the North End Point well. It is to be expected 
that to the eastward the materials of this horizon finally become too fine 
grained to carry water, and the eastern limits of conditions favorable 
for water bearing appears to be at Clay Bank, on York Eiver. Probably 
the well now being bored at Norfolk will throw light on the question, 
although I do not really expect Pamunkey beds to be sufficiently coarse 
at that locality to yield water in large amount, and have advised that 
the boring be planned to go to deeper horizons. 
Water also occurs in sands in the Pamunkey formation about 90 feet 
above its base, as indicated by the water at 160 feet at Colonial Beach, 
and at 275 to 325 feet at Naylors Wharf ; but as it has not been further 
explored by other wells, its extent can not be discussed. 
CHESAPEAKE. 
Lying between the clays, marls, and fine sands of the Chesapeake 
formation and the top of the Pamunkey formation, there is a series 
of sands and gravels which may be regarded as the basal bed of the 
Chesapeake formation. To the eastward this series contains thin inter- 
stratified rock strata which do not appear in the surface outcrops. In 
this series, and in another similar one not far above, there is a large 
volume of water, at a horizon or horizons which appear to be of wide 
