The republic. [volume] (Washington [D.C.]) 1849-1853, 1851-04-25
TO CONTRACTORS

OFFICE OF THE CORNERSTONE OF PusLrc BUrLpINas
WAsHIHaToN, April "a, 1851.
PROPOSALS will be received at this office until
i IL o'clock, m, on tho 10th day Of May next,
for constructing bridge across Tiber creek, ut its
intersection with New Jersey avenue and D street
north. The bridge. when finished, will be liz feet
long, with elliptic arch Of - feet span and 81
feet rise from its springing.
The pit for the foundation must be excavatcd to
such depth superintendent of the work, to be APP
pointed by the Commissioner, may direct. A foun-
square, will then be laid three feet from centre to
centre, transvcrsely to the axis of the arch, ex-
tending to the back lines Of the side walls Three
rows OF sheet Piling, three inches thick and five
feet long, will then Be driven the upstream sides
three of the logs viz One in the centre and at
each cndofthe pit, and quite acrossi, and wespiked
to the logs; a piece Of timber, 10 by IL inches
square, will then be notched one inch into the trans
verse logs for the whole distance of the culvert on
both sdes at the line Of the face of the side walls
the inner edge of which ia to be chamfered, and be
properly secured to the foundation timbcrs; floor
ing three inches thick, of Carolina or Georgia pine,
will then be laid oyer the whole surface Of the cun
dation timbers, and secured to them by wrought
iron spike through each plank into each log 1t may
cross and, in addition to this, tree nail Of oak
locust, Il inches square and IA inchcs long, must
be driven into each log, through each plank,
cept those under the side walls.
The side walls will probably be about six feet
high from the floor to the spring OF the arch. The
arch will then be laid eighteen inches deep, after
which the side walls will be carried up to its crown
filing the arch to its crown with solid mason
ry. The side walls will have average thickness
OF four feet.
Parapct walls, ID inches thick and 8, feet high,
will then be carried up upon airing course Of
cut granite inches thick. the whole TO be COPIED
with good sandstone inches thick at the edges,
with saddle back Of two inches. Wing walls
will be laid 30 far as may appear to be necessary
the average thickness Of which will be 81 feet.
The arch and parapet walls will be Of the best
hard brick; all tho other masonry will be Of large
size blue rock gnciss, and the whole to be laid in
mortar made of lime, sharp sand, and portion Of
hydraulic cement, except that the side walls, on
which the arch is to rest must be laid, for foot
from the face and four feet high, in hydraulic &C.
ment and suitable quantity Of sharp sand, with
out any quick lime.
The whole of this work is to be done in the best
manner and of the best materials, under the direc
ton Of the before mentioned superintendent, and
to be completed by the frat day of September next
Persons proposing will state their price per cubic
yard for excavation of the foundation; per 100 feet
board measure for the flooring and piles; per cubic
foot for the squared timber; per perch of IS cubic
feet for the stone masonry; per thousand for tho
brick laid; per foot lineal for the granite string
course, and per foot linca for the sandstone coping
including all materials, ccntring, Golfer dams,
tools, &c. And no proposal will DO considcred
which does not fully conform to this requirement
A contract will be entered into, and bond with
security will be required for its faithful perform
ancc. Persons offering will, therefore, please to
give the names Of their proposed suretics.
Tho Commissioner reserves the right OF reducing
the length Of the bridge to 80 feet.
Any further information can be obtained by APP
plying at this office, where the plan may be seen.
WIN. EASILY,
Commissioner Of Public Buildings.
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