The morning call., 1893-08-23

not proceed. Other delays procured for
the contractor an extension Of time, and
when be was all ready then the approaches
on the north side had to be fixed. The
adjacent property-hOlders refused to do
this. as required, and the Street Superin-
deut advertised for bids, intending to do
the work himself, but he was blocked by
protest from the pToperty-o
so the matter stood yesterday. The
north-end approach presented very dan
Rerous appearance. 1t Is full of holes,
some of which are large enough to engulf
a horse and buggy. The planking is Jag
gedly uneven, and the piling requires
looking into. Still. with little patching
up it might be rendered available for
pedestrians until the board accepts the
bridge and settles the matter OF the thor
ough repair of the approaches.
The testing yesterday was left to the
'eDgineers in charge" formerly the Board
of Engineers, headed by Marsden Man
son, who, mDanied by his rodman,
Elmer A. Wolfe, appeared on the scene
about P. N. There were also present
Street Superintendent Ackerson and his
deputy, Fltzge raid the planning engineer,
Alfred ID. Ottewell; the contractor, 3.
Mcmahon, aud Inspector Hendry. None
of the Supervisors were on hand. There
was big attendance CT people curious to
observe the process of testing.
A preliminary test of the bridge ma
CulHSEy III LILO Hdu
some difficulty in turning so that the
present test was all the more interesting.
The disposition of the immense piles of
sand bags on either bank of the stream
had also to be watched.
Briefly stated. the testing of bridges is
either done by means Of dead or living
weight. The latter consists of running
load across the bridge. In this case the
dead weight was tried. The levels of the
piers are carefully taken, the weight is
placed on the bridge and left for sta ted
time; the levels are then carefully taken
again, and any variation shows a settling
OF the piers or other defect.
In this case the spectators watched
Marsden Manson with a theodolite take
the levels, and then the bridge, which
until then had remained parallel with the
stream, was swung slowly around into
position. Manson once more took the
levels of the bridge upon the piers and
then ten men on either side began to
truck the heavy bags of sand. upon the
bridge. beginning at the center and plac-
ing a single layer evenly over the entire
surface.
From the supervising engineer il " as
learned that no less than 245 tons of sand
were called for by the test. 1t came in "a
wagon-loads of 212 tons each. a sack aver
aging 180 pounds. The weight thus i'm
posed was equivalent to eighty pounds to
the square foot. For this bridge living
weight of forty tons would be required, but
should this dead-weight test prove salts
factory the 1iylng-weight test would be un-
necessary.
Superintendent AckersOn said that he
was not quite satisfied as to the way the
bridge worked. Apparently the contractor
had faithfully followed the specifications,
but they might have been defective. The
gearing did not seem quite heavy enough.
and that might indicate too great cheapneSs
of construction. There was also a rough
ness in the working OF the machinery He
thought this weight test unnecessary as
the plans showed the bearing capacity.
This was nothing but theatrical waste of
money.
Mr.. Ackerson was indignant at the deay
in the bridge opening and attributed it to
the Supervisors. He said that as soon as
the pending protest was dealt with he
would have the approaches put IN per-
manently good shape. In the meantime
he would have red lights placed on either
side OF the bridge and a watchman de-
tailed for the protection of the public.
Contractor Mcmahon said he was per-
fectly satisfied with the working of the
bridge. he was not responsible except as
tofollowing the plans of tile design. Every
detail OF the specifications had been ad-
hered to.
Consulting Engineer A. d. Ottewell.
who designed the bridge. said he was
pleased with the way in which the machin-
cry bad behaved. 1t had worked a little
roughly. as all new machinery would. and
the regular engineer, Hendry, was un-
avoidably absent. Also, the two revolving
circles might not he perfectly concentric
by the amount of, say, the eighth of an
inch. Stteh variations often occurred in
the bending of thick iron bar but would
not affect the practical working of the gear
ing. Use might relieve the roughness to
some extent.
A large number of people used the bridge
as soon as it was in position, showing its
need. One lady crossed while the struc.
ture made it's first experimental circuit,
and as it was starting on its second round
feared that there was cons piracy tC
strand her in the middle of the stream
She made rush and saved herself by an