daeton.] MARYLAND. 145 
at this locality yield a largeauiouiit of excellent water, which does not 
appear to contain surface contamination. The following record is given 
for one of the wells at the potteries : 
Feet. 
0-20 black mud. 
20-30 yellow loam. 
at 30 gravel ; full of water. 
30-41 yellow clay. 
41-45 hard ''kaolin." 
45-50 white gravel, full of water. 
The well on West Falls avenue, near Alice Anna street, obtains water 
from sands about 42 feet above bed rock, no doubt in the B horizon; 
and the Duker wells, a few blocks northeast, have a depth of 90 feet, 
probably to about the same horizon. The water of the first is brackish, 
and that of the latter, although formerly in large supply, is now greatly 
decreased in amount. In the region immediately adjoining Jones Falls 
and for some distance to the westward on the north side of the Basin 
deep wells do not yield satisfactory water supplies, on account of prox- 
imity of the basal and lower Potomac beds to the surface. Several 
wells have penetrated the crystalline rocks, notably the one at the old 
Maltby property, at the foot of President street. This well was bored 
to a depth over 900 feet, and found, I understand, a fair supply of satis- 
factory water. The Tyler well, at the foot of Luzerne street, appears 
to have penetrated the rock for some distance, and it furnishes a large 
supply of water, but I could not ascertain whether the water came from 
the rocks or the overlying beds. 
A recent boring at the Bartholomay Brewing Company's building on 
Central avenue, near Gough street, encountered " quicksand" at 320 
feet, which could not be penetrated with the means at hand. This 
boring was in the crystalline rocks from 250 feet down. 
Region between the basin and harbor and the Middle Branch. — There 
are several wells along the north side of Locust Point to Fort McHenry. 
which yield satisfactory water supplies from the Potomac horizons, 
The wells at the marble works at the south end of the basin reach 
basal Potomac beds at 160 feet, and extend into the bed rock to 200 
feet, but they do not yield much water. Wells less than 100 feet deep 
at Dunnington's, Moore & Brady's, and Beacham's shipyard draw from 
a horizon about 30 feet above bed rock, and this same horizon is reached 
at 150 feet in the well at the paper mill on top of Federal Hill. At this 
mill the rock was found at a depth of 180 feet, and penetrated to 402 
feet without yielding additional water. 
At Moore & Brady's Packing House, foot of Montgomery street, 
there is a well 53 feet 7 inches deep which yields a large supply of pure 
water. It is reported that sand extended from the surface to 30 feet, 
and clay from 30 to 53 feet. The water is in a gravel and sand bed of 
which I could not learn the thickness. The well borer stated that the 
rock was found under blue clay at 85 feet, and that it was penetrated 
to 135 feet without finding additional water. 
Bull. 138 10 
