6 GAZETTEER OF MARYLAND. [bull. 231. 
landward side. On the west side of Chesapeake Ba}~ the Coastal Plain 
reaches an altitude of 300 feet in places, and shows much relief. Of 
the twenty-three counties of the State, the following - are comprised in 
the Coastal Plain: Worcester, Somerset, Wicomico, Dorchester, Caro- 
line, Talbot, Queen Anne, Kent, and Cecil, on the peninsula, and Prince 
George, Charles, Calvert, St. Mary, and Anne Arundel west of Chesa- 
peake Bay. 
Along a line running- through Havre de Grace, Baltimore, and Wash- 
ington the granitic rocks rise to the surface. This is called the "fall 
line," from the fact that streams have rapids or falls where they flow 
across the first hard ledges. West of this line granite or allied rocks 
predominate, while east of it, on the Coastal Plain, are soft Cretaceous 
and Tertiary formations. This region extends from the fall line to 
the Blue Ridge and has an area of about 2,500 square miles. It is 
known as the Piedmont Plateau and comprises the following counties: 
Montgomery, Howard, Baltimore, Harford, Carroll, and Frederick. 
This region presents much more relief and is higher than the Coastal 
Plain. 
The third zone, that of the Appalachian Mountains, extends from 
the Blue Ridge to the west boundary of the State, and has an area of 
about 2,000 square miles. It includes the counties of Washington, 
Allegany, and Garrett. In the main this region consists of an alter- 
nation of valleys and mountain ridges, the latter rising to altitudes of 
2,000 and 3,000 feet. In the western part, mainly in Garrett County, 
is a plateau with a rolling surface 2,500 feet above sea level. 
The mean elevation of the State is estimated at 350 feet. The areas 
in different zones of altitude are as follows: 
Elevations in Maryland. 
Square miles. 
Sea level to 100 feet 7, 400 
100 to 500 feet 2, 000 
500 to 1,000 feet ". 1 , 700 
1,000 to 1,500 feet -300 
1,500 to 2,000 feet 410 
2,000 to 3,000 feet 400 
Maryland was first settled in 1634: under a charter to Lord Balti- 
more, settlement being made at St. Marys. It was one of the thirteen 
original States, having adopted the Constitution on April 28, 1788. 
In 1791 the State ceded to the General Government for the purposes 
of a capital an area of about 70 square miles, which constitutes the 
present District of Columbia. The following table shows the growth 
of population in the State from the first census in 1790 to the latest 
in 1900: 
