1850 (approx)  Operated by the Seneca Sandstone Company. 2

1867 Operated by the Potomac Red Sandstone Company. 2

1870 The greatest number of men employed by the quarry and mill. 3 

1871 The canal transported 850,000 tons of stone. 3 

1891 Operated by the Seneca Stone Company 2

1893 Seneca Stone Company paid $833.33 for the use of waterpower from the canal. 1

1900 Quarry operations were stopped. 1

Bibliography

ACHS Summary Form

1:  The Smithsonian Journal of History, Vol. III, Spring 1968, pp 41-58

2: Landmarks Research Form by Bob Kasparek

3: Seneca Creek Sandstone: Its History and Use as a Building Stone by Kristin Fetzer, 1997

4: Building stones of our nation's capital      U.S. Geological Survey

In 1871 the canal transported 850,000 tons of stone.

Seneca Quarry & Time Line Cont.

Seneca Stone Cutting Mill | Seneca Quarry and Cutting Mill

Time-Line | Time Line Continued | Directory of Related Links | Seneca Stone Response