DELAWARE. 
119 
PAMUNKEY FORMATION. 
The weathered brown sands of this formation, a few feet in thick- 
ness, exteud only a short distance into the western side of the State, 
but it is probable that the formation thickens to the south and east 
under the Chesapeake beds, for it outcrops over a wide area in the 
adjacent Maryland region. 
CHESAPEAKE FORMATION. 
All of central and southern Delaware is underlain by this formation, 
of which the edge extends to within about 2 miles south of Middle- 
town. On the southern border of the State the formation probably 
has a thickness of about 1,200 feet. It consists mainly of clays and 
fine sands of the same character as those in southern ]S"ew Jersey. 
The great diatomaceous clay bed, which is over 300 feet thick in the 
Atlantic City, Ocean City, and Wildwood wells, continues southward 
across Delaware, apparently with slightly increased thickness. It 
appears to be associated with similar water-bearing sands, but as few 
wells have been sunk in Delaware these sands have not been so defi- 
nitely located as in New Jersey. 
COLUMBIA FORMATION. 
This formation covers all of the State south of the Baltimore and 
Ohio Kailroad. It is a mantle of gravels, sands, and loams which caps 
the terrace plain to a thickness of from 10 to 30 feet, the amount increas- 
ing somewhat southward. 
DEEP WELLS IN DELAWARE. 
There are only a few deep wells in the State, but they are all success- 
ful and nearly all furnish large supplies of water. In the following list 
are given all those of which I was able to learn. Their location and 
horizons are indicated on the map, PI. V: 
List of deep wells in Delaware. 
Locality. 
Depth. 
Diam- 
eter. 
Capacity per 
minute. 
Height to 
which water 
rises. 
Remarks. 
Dover 
Feet. 
196 
35 
Inches. 
10 
6 
Gallons. 
/ Flows 35\ 
\ Pumps 218/ 
30 
Feet. 
+ c 
+ 20 
Clayton 
Do 
no 
Do 85 
Water also at 40 and 60 feet ; 
105 
rock at 211 feet. 
Kitts nummock 
110 
400 
20G 
535 

10-6 
Much. — 2.V 
Mahon River 
Much. 
330 
Middlotown 
—50 
Fine quality of water; much 
water also at 475 and 540 
feet. 
