MARYLAND GEOLOGICAL SURVEY 149 



flow that derive their supply of water from Potomac strata at depths 

 between 100 and 112 feet. At Bladen sburg flowing wells with 

 capacities ranging from 1 to 15 gallons a minute have been obtained 

 at depths between Y3 and 100 feet; at the plant of the National 

 Capital Brewing Company there is a 103-foot well that yields from 

 100 to 130 gallons a minute; at Langdon a flow of 40 gallons a 

 minute was obtained at a depth of 140 feet ; at the Reform School 

 water Avas encountered at a depth of 270 feet; and near Chesapeake 

 Junction a well which formerly flowed but now has to be pumped 

 obtains its supply of water at a depth of 350 feet. In adjoining 

 regions the Potomac strata have yielded an abundant supply of water. 

 At Annapolis, on the grounds of the United States jSTaval Academy, 

 a well sunk to the depth of 601 feet penetrated eight water-bearing 

 strata within the Potomac beds, from three of which water flowed 

 out at the surface, 8 feet above tide. At the lowest horizon, between 

 587 and 601 feet, a flow of water of 75 gallons a minute is obtained. 

 The water contains iron, but is of excellent quality when filtered. 



Waters of the Upper Cretaceous Formations. — The sandy strata of 

 the Earitan and Magothy formations are in many places water-bear- 

 ing. The water is apt to be strongly impregnated with iron, and 

 locally with sulphur; consequently it is less desirable than that 

 obtained from the Potomac deposits. At Upper Marlboro several 

 flowing wells with an average depth of about 225 feet obtain a good 

 supply of water from the Magothy. In some of the wells the amount 

 of mineral matter in solution renders the water somewhat undesirable 

 for drinking purposes, while in others the mineral matter seems to 

 be present only in very small amounts. The ISTaval Academy well 

 at Annapolis obtained flowing water from the Magothy at a depth 

 between 180 and 220 feet, but as the supply was not sufficient the 

 well was sunk deeper. 



In ISTew Jersey considerable artesian water has been obtained from 

 the greensand deposits of the Upper Cretaceous. In Prince George's 

 County no artesian wells are known in which the supply of water is 

 obtained from the Matawan or Monmouth deposits. These are in 

 general more porous than those of the Magothy or Potomac forma- 



