New-York tribune., 1908-05-29
INTESTIGATION AT LAST.

The city administration is to be c0ngrat-
ulated on finally coming TO a realization of the
necessity for A thorough and impartial exam
ination of the Blackwell's Island Bridge When
The Tribune first called attention to the
changes of plan, and the added weights which
promised TO result in placing strains greatly in
excess of those under which the Quebec Bridge
collapsed on compression members so designed
that many competent engineers considered them
inferior 10 those of the Quebec Bridge and also
inferior to the original plans Of Mr.. Lindenthal.
on which the contract was let, the city officials
pronounced the charges absurd. The Mayor, IN
a humorous vein, asked to be invited TO the
spectacle of the falling bridge. An attempt
was made to evade the issue by statements on
immaterial points, such as the demonstrated
strength Of the tension members, which had not
been called in question, and appeals to prOfes-
Sional authority which, on investigation, was
not found to be any guarantee whatever for
the safety of the bridge. So strong, however.
was the case presented by The Tribune, with
out the aid OF any other newspaper, that in
spite of the success of the officials in prevent
ing the subject from becoming matter of gen
eral discussion in the press they soon lost the
courage of their cbstinacy and have now
done practically what The Tribune at the be-
ginning urged them to do for their own prOtec-
ton and for the public safety. They have not
yielded gracefully. but they have yielded, and
that is the point.
The men who have been selected by the
| Controller to make this investigation have
high reputation for professional skill and sturdy
! professional character They promise to start
at the beginning. taking no ones ready made
| figures, and make independent calculations of
| their own. based on the actual structure that
| they see before them, aud finding out the actual
strains which the bridge must endure. Then
| they will make practical tests to if the
preston members are equal to the work re-
quired. They will doubtless also throw much
| light the reasons for some of the changes in
design which scarcely eXplicable-at
least from the point of view OF the city. They
may discover if there is any reason. except to
increase the profits of the contractor. for sub
stituting four leaves each a of an inch thick
and 1872 inches deep for three leaves each 70
inches thick and 60 inches deep in each of the
four webs of the main compression member
thus reducing each web J.. inch in thickness and
11l2 inches in depth, making them lighter than
the corresponding members Of the Quebec
Bridge. 1t is clearly mlrh cheaper for the con
tractor TO roll steel plates q Of an inch thick
and avoid blowhoes and make them pass the
test than TO roll IL Inch plates. The investi-
gators may find out if the thin plates though
cheaper. are stronger as strong. 1t is also.
of course. obvious that it is much cheaper for
the contractor to make his compression member
in two parts and fasten them together with
diaphragms instead of fabricating the four
webs into one box girder From the contract
ors point Of view these changes are easily I'm
derstood. Perhaps Messrs. Boiler and Hodge
may be able 10 find out what was the advan-
tage Of the changes TO the city
The original price pound for the steel work
was based, Of course Oh the cost Of making plans
and providing necessary machinery and erect
ing cranes and the either investments necessary
10 put up the bridge. The investigators may
based all these expenditures was or was
not excessive for the large additional amount Of
steel ordered If, all these costs OF the work
as a whole having been distributed and paid
for in every pound OF steel as originally pro-
yided in the contract the additional steel was
not an exceedingly fat piece Of work for the
contractor. 1t viii scarcely fall within their
province as engineers 10 discuss the legality of
the payment for this additional work of thou
sands of dollars in violation of the express
terms OF the contract; nevertheless, by the time
they have finished their study light may he
thrown Oh this phase Of the subject.
Altogether the bridge matter is placed on
before said, it has not taken up the subject for
q newspaper sensation. 1t is not seeking 10
make political capital has it any personal
animus against the Bridge Commissioner or
those associated with him in his work. We
give him full credit for believing that the bridge