The times. [volume] (Washington [D.C.]) 1897-1901, 1900-04-10

The Secretary Of War sent to both
Houses of Congress the report Of the
| Board Of Army Engineers and Architects
appointed last February to receive and
| recommend plans for a memorial bridge
| across the Potomac River. extending from
the old Naval Observatory to point di-
lecuy across the river on the Old airing
ton estate. The board recommends tne
construction Of bridge which will cost
about - 500 900
The report reviews at length the plans
submitted by four prominent bridge arcni-
tects and engineers. and selects those OF
William II. Burr. OF New Yorh, as con-
forming most closely to the general speci-
! hcations called for.
BY an act OF Congress passed during the
last session money was appropriated for
prizes 10 be given to architects and bridge
engineers submitting the most appropriate
and suitable pans. Four prizes were Of
fered.
The general outline specifications gov
erning the competition. issued under date
of July q. 1899. called for the presenta-
tion OF two designs for bridge with a
draw opening: one design TO provide for
street cars as well as for ordinary vehicles
and for pedestrians. the street ears to be
below underneath the highway. The
width OF the structure TO be sixty feet,
including sidewalks. Material mainly
granite and steel The second (altcrnatel
design to be for q bridge with draw open
ing. but without provision for street ears.
The question whether street cars should
be allowed upon the bridge being m iln'
portaut one and admitting OF considerable
difference Ia opinion. 1t was deemed best
that designs should be submitted for cnch
kind OF bridge in order to make brticr
comparison OF their architectural chrct.
adaptabilty and cost, respectively
The designs and drawings were TO be
paid for in the order OF merit Of the de-
signs. as recommended by board Of en-
gineers. and approved by the Secretary oi
War. as follows:
For No. ! 81 200: for No .. $l.l00, for
No 3. 81 coo. for No. 4. 5000.
The designs. drawings and estimates
were then to become the property ot the
United States.
MIR. Burr's design, the one approved by
the board with a few alterations, is sum
married. in the report as follows:
This is a design for a single-deck
bridge so feet in width between ratlings,
providing for two sidewalks, each 10 feet
vide and a roadway 40 feet wide. This
design makes no provision for street rail
way tracks. The total length Of the open
work of the bridge proper ard approaches
is about S,4OO feet.
THE bridge proper is to consist of three
192-foot span masonry arches. one steel
draw span having a clear width OF log
feet. and three more 192-foot span ma
sonry arches
The 192-fOot masonry arches are circu-
lar (seEmentaD. the springing line being
q feet above mean low water. the rise
above the spring % feet, and the radius OF
the ntrados 1888 feet.
The clear head room under the crown OF
the arch is So feet clear head room OF
about 81 feet at low water is provided un-
der three arches for a width Of 80 feet at
the centre and of about A. feet 4 inches
for a width Of 100 feet. The face OF the
arch ring is Of granite, but the construc-
tion OF the main part Of the ring Is on
the Melan system, there being five main
concrete steel ribs. The granite arch ring
is ; feet inches deep at the crown and
. feet inches deep at the spring, while
the concrete steel ribs are 30 inches deep
at the crown and feet inches at the
spring A solid masonry spandrel wall.
partly of granite and partly Of concrete
rests upon the granite arch ring. The
asphalt roadway and granolithic sidewalks
are supported by concrete floor arches be-
tween I-beams The weight Of this floor
system is carried down to the arch ring
by framed steel posts. between the above
masonry spandrel walls.
The draw span has two bascuie arms
supported on trunnions. balanced by rear
extensions and counterweights. The clear
opening is about 1875 feet. the clear span
al low water level 159 feet, and the span.
from centre TO centre Of trunnions, 40
feet. The bascule arms are composed Of
five steel trusses of the lattice girder type
with parallel cords twelve feet six inches
deep between centres. The clear head room
is about hfty-one feet when the draw is
closed The floor is to be of asphalt cork
blocks nodded to fit the buckle plates,
which are supported by the floor beams and
stringers carried by the trusses. 1t is pro
posed to operate the draw by four fifty
horsepower electric motors.
The Washington approach is to consist
Of twelve sixty-foot span masonry arches.
back of which is an earthen embankment
about $50 feet long
The sixty foot span masonry arches arr
full semi circular. the springing line being
twenty-four feet above low water. the rise
above the spring thirty feet and the radius
OF the intfados thirty feet. The arch is
constructed Of the same materials and in
The same manner as the 1872 foot masonry
arch above described. The granite arch
ring is four feet deep throughout, while
the concrete and steel ribs are sixteen
inches deep at the crown and forty-eight
inches deep at the spring"
The principal divisions Of the bridge are
marked by massive masonry arches and
towers. decorated with emblamatic groups
of statuary Upon each Of the bsscule
piers is erected a single arch transverse
with the roadway. This constitutes the
most prominent decorative feature Of the
bridge
After a careful consideration Of the
architectural features ornamentation, and
cost Of the plans the board has decided
upon the following order OF merit.
No. design No . Of William r. Burr
No. .. design No. OF William r. Hut
ton
No. 3 design No. / OF L. L. Buck.
No. 4. design No. 1 Of George S Mori-
son.
All of the foregoing architects are from
New York City and were especially re-
ouested by the Secretary Of War to enter
Tho competition. The board OF engineers
and architects in whose hands rested the
Judgment Of the merits of the plans con-
sisted Of Lieut. Col. Charles j. Allen.
Major Thomas ". Sy mons and Capt David
DUB. Gailard all Of the Corps of Engn-
eers. L. S A.; Mr. Stanford White. Of
New York, and Mr. James G. Hill. OF this
city.
FUNERAL OF GENERAL BACON.
Private Services and Interment of