Evening star. [volume] (Washington, D.C.) 1854-1972, 1872-05-27
AND SOUTH.
ANOTHER TIEAN IRON ONE.
The New Railroad bridge Across the
Potomac.

Inc new railroad br1o&G ACROSS the
Potomac.
The new bridge across the Potomac river on
;ae site of the old Long Bridge, is now receiving
TIE fin ishing teaches. 1t is already open TO
pgblic travel, and in use for the accommodation
OF ped sstTians and equestrians, as well rail-
road tI aims. The new structure Is one of the
, most Substantial railroad bridges in the coun-
. try, an reflects credit upon the engineer, Mr.
j. A. p artrsge, and others who took part in its
eo1stru ction. The Baltimore and Potomac rail-
, road company obtained possession of the old
= bridge 'snder an act OF Congress about a year
and b alt ago, and Immediately thereafter Mr..
Psrtridg &c prepared his plans, which were ap-
proved, and the work was commenced. The
. entire structure is
NEARLY NILE IN LENGTH,
with an average width of over 40 feet. u is
. eo1nposs, I'd of two kinds of wUrk-the Howe truss
and The caussway. Ihs latter Is on the site Of
but the new is five feet higher than the old
work. The truss-work is also higher than the
old wood work. The causeway is 1903 feet in
lenGth, the walls being Of solid masonry 2S feet
thick rip raped on both sides IA feet above low
water The space between the walls and rip
rs9plng Is FILED in with earth, which, having
been allowed to settle as the work progressed,
IS yery compact. 1t is covered with the best
quality OF gravel, u inches deep, which makes
very smooth roadway for vehicles. On the
side OF the causeway is plank foOtwalk, rest
ing on oak brackets projecting over the wall.
The brackets made fast TO the coping. A
neat railing is on the side next the water. This
u
ptOper being 10Y feet.
WORK ON THE WASHINGTON SIDE.
Leaving the retaining wall, 1870 feet in length,
at dis (the Washington end of the bridge,
which. like all the other stone work, is laid in
hydraulic cement, we arrive at the first abut-
meut, ASH feet in length and 1Gfeet high, which.
with the first pier, supports the first span OF
Howe truss rs feet 3 inches in length, while
seco1d pier on the north side OF the channel sup
ports the second span similar TO the first, but ~
feet lOnger. In the center of the channel is 2
niles which q
cu!ar pier 81 feet in diameter, and on this is a
nicely balanced iron draw-known as the War
rem glider draw-122 feet i'm length and - feet
wide, worked by pinion OH a circular rock, and
so nicely balanced that one man can easily turn
1t. An abutment pier. similar to the one at the
north end of the draw, receives the south end
of il, and with two other piers and the abutment
of the caIseway supports three spans of Howe
truss respectively 1i2 feet 2 inches, 40 feet ~
inches and iol feet inches in length.
THE PILES
are all well Tip-rapped. with the exception of
those facing the north side of the Washington
channel where IS feet OF water is left at low tide
Those at the northern end of the causeway are
60 feetloDg-that length being required from
the nature of the bOttOm-to reach a firm fOun-
datlOn; but all the others in 40 feet lengths,
and were mostly furnished by Capt. Troth, of
Accotink, Va. Before they were driven they
were tipped with an iron point. and the work of
driving them was very tedious, five rows being
required for each pier, two feet intervening be-
tween each row. After these were driven home
into a hard, gravel bottom, they were sawedoff
squarely about feet below low water marian
ingenious device Of Capt Partridge. the engi-
ncer, being used Cor that purpose. This appa-
ratus consisted OF circular saw on al upright
iron shaft constructed on fiat boat, and worked
by six horse power engine, and the work was
done by IL with remarkable celebrity and
ease. After the tops, were made level, oak tim
bers, IA inches square, were laid across them,
through which heavy iron bolts were driven into
the piles, making thea secure On the top of
these timbers a flooring OF u inch oak was laid
and bolted down, and On the edge piece of the
-,F~z
were, a box OF u inches depth. This was nearly
filled with concrete-bTOkens stone and cement
which in a short time becomes as hard as granite
Itself. On this comes the masonrSOf the best
gualty-cut sand stone from Aduia creek and
Freestone Point, laid in cement mortar. The
piers are 4SH feet long and feet wide,
of the highest floods ever known in the Potomac.
On these piers rest immense wooden stringeTs-
the best Susquehanna pine wharf tImbers, 16
inches square-well joined and bolted; the ends
lodging in oak wall plates of 10 inch timber.
The flooring of the bridge is inches thick, and
will last for years. From the stringers rise what
= known as
THE HOWE TRUSS BRIDGE.
That portion north of tie Washington draw is
2 feet in height above the stTingeTs, and uncov-
cred. The remainder is 81 feet high above
striHgers, and il is likely at some future dAy il
will be covered. This truss work is built of
immense timbeTs, bolted with wrought iron rods
OF over four inches diameter. Much of the work
was done under water and il was found neceS-
sary to secure the services OF one of those
amphlbious Personages-a professional diver.
SOUTH OF THE CACsRWAY
there are eight piers. similar TO those on the
nortb side, on which, with the abutinents there
are nine spans OF n foot high Howe truss, each
81 an 40 teet y inch in length, reaching the
Virginia draw. This draw, like the other, rests
or circular pier, "a feet in diameter, and is Of
ir50-s y foot Howe truss. weighing 20 tons.
1l'5t -! length of this draw is III feet inches,
one Lei.s 90 feet6 inches, and the other -
feet Ies, and il requires about 1870 tons of
iron On tie shD.t end TO balance the longer arm.
This plan OF G-aw was adopted because the
Alexandria railroad bridge would have prevent
bridge having been damaged, and it having
recently passed into the hands of the Pennsg :
varia Central railroad II is probable il will be
removed and the short end OF the draw
heightened out Ike the draw on tie Wash
ing on side. this is so nicely balanced that re-
quires but little power TO work it. The water
ia the channel here is 80 feet in depth at low
tide. On the south siEs of the draw the Howe
truss work continues il four spans-two of 13S
feet = inches long, al two of l37 feet =
inches long. bringing W 20 the retaining walls
OF the Virginia causeway tj0 feet in leDgth. The
Howe truss IL IL feet wide, the roadway 20 feet
IN me clear, and tAat porr.on occupied by the
track Is feet.
Thus the work consists of - piers besides the
two large circular draw piers, I abutments, 2
retaining walls, ,963 feet in length OF cause
way, spans of S-foct Howe truss, draws
aggregating 266 feet long, and IS spans (2 .6T5
feet aggregate lengthy of 21-foot Howe truss,
An ll-foot board fence is built the length of the
caHseway. to keep horses from being frightened
by the trains. Some idea Of the amount of piling
may be obtained when we state that it is esti-
mated that IL the piles used TO support each
draw were placedsin straight line tiey would
extend distance OF five miles. During the
work on this bridge the company have had at
times as many a. 500 hands employed, besides
those al the auarries, and the work h2s gone
regularly ON during all sorts OF weather. The
masonry was done by Campbell Brothers, OF
Pennsylvania, well known railroad contractor.
aud they completed il inside of twelve months.
Inc Howe truss was erected by the Keystcua
bridge cOmpany-hfr. Brooks, superintendsat.
The immense tiLnbers, before being put in
pace, were all fitted together ON the Virginia
shore. The remainder of the work, incIudiny
the pile-driving, was done by the COMPANY
MIR. John BreniZer experimenting. Since the
bridge was opened the travel over it has been
immense, particularly during fine afternoons.
CHARACTERISTICS great tragedienne COM
mences an engagement here tO-nighf at The