DESCRIPTIONS   OF   BENCH   MARKS
 

BOROUGH   OF   BROOKLYN.

B. M. 178.—Fort Lafayette. A 2-inch square (xl) cut in the top of the outshore
edge of the sea wall on the south side of Fort Lafayette. The point is opposite the
boiler shop and 38 feet south of the southwest corner of the carpenter shop.

Elevation, 8.131 feet

B. W. 179,—Fort Lafayette. A cross (-|-) cut in the top of the sea wall on
the east side of Fort Lafayette. The point is just east of the carpenter shop, and
10 inches from the east edge of the wall. It is 5.4 feet east of the high iron mooring
post and 18 inches south of a small ring bolt in the wall. The figure 164 is cut
alongside of the point.    (Note 17, p. 91.)

Elevation, 8.013 feet.

B. M. 180.—Fort Hamilton. Coast and Geodetic Survey B, M. 1, formerly known
as B. M. S. It is the top of the tide staff established by the Coast and Geodetic
Survey on the north side of the tide house on the south side of the government
wharf near its southwest corner. The bench mark corresponds to a reading of 12
feet on the staff. It should be noted that the tide staff is movable vertically and that
the 12-foot mark is the bench only when the staff is in its lowest position. Estab¬
lished in May, 1905.

Elevation, 6.040 feet

B. M. 181.—Fort Hamilton. Coast and Geodetic Survey B. M. 2, formerly known
as B. ;\!. A. It is a 6-inch cross (+) cut in the top of the granite capstone on the
west edge of the old stone pier, and 6.85 feet from its southwest corner. It is 1.5
feet from the west edge of the pier.    Established in October, 1892.

Elevation, 8.855 feet

B. M. 182.—Fort Hamilton. Coast and Geodetic Survey B, M, 3, formerly known
as B. JI. B. It is the top of an iron mooring post at the southwest corner of the
old stone pier, 3,75 feet above the wharf.    Established in October, 1892.

Elevation, 12,677 feet.

B. il, 183.—Fort Hamilton. The top of an iron mooring post near the north edge
of the old stone pier and just south of the one-story frame boathouse. The post is
3 feet from the north edge of the pier and 43 feet from the west edge. It is 4 feet
from the southwest corner of the boat house and 3.75 feet above the wharf.

Elevation, 12.601 feet

E. M, 184,—Fort Hamilton. Coast and Geodetic Survey B. M. 4, formerly known
as B. ^I. C. It is the top of an iron mooring post near the southeast corner of the
widened end of the old .stone pier. It is 3,75 feet above the surface of the wharf.
Established in October, 1892.

Elevation, 12,598 feet.