What is "martin's additions"

Population (2000): 875
Housing Units (2000): 312
Land area (2000): 0.134108 sq. miles (0.347338 sq. km)
Water area (2000): 0.000000 sq. miles (0.000000 sq. km)
Total area (2000): 0.134108 sq. miles (0.347338 sq. km)
FIPS code: 50965
Located within: Maryland (MD), FIPS 24
Location: 38.979713 N, 77.069349 W
ZIP Codes (1990):
Note: some ZIP codes may be omitted esp. for suburbs.
Headwords: