The New York herald., 1877-01-13
THE BROOKLYN BRIDGE.

CONSIDERING THE soUNDNEss OF ITS sPEcIFI-
cATIoNs-wHAr MR.. ALBERT HILL THINKS
OF THE STEEL TO BE USED.
In view of the meeting OF the Board of Trustees held
on Thursday last representative OF the HERALD yes
terday called upon Mr. Albert Hill to inquire his opin
ion Of the proceedings which there took place, ana
more especially the arguments OF Colonel Paine and the
Chief Engineer respecting the kind of wire to be used
In the cables. When asked If he had read the reports
Of the meeting he replied
"Ycs, have heard OF that meeting, and am also
cQgnzant Of the Of Colonel Palnes answer and
the report oil the Chief Engineer OF the bridge Unfor
tunately Colonel Panc's remarks really answer
at all to my statements but simply general denial OF
their correctness"
YALLAcIEs OF COLONEL PAiNE's REPORT.
"Will you please to specify your objections to the
ground assumed by Colonel Paine 2"
'Ccrtainly. In the first place. Colonel Paine takes
exception to my argument against their right OF
suming steel of given density. He says:-'Now
mua. however correct be applied this unless
the specific gravity Is other ascerlaned assumed
II an assumption Is not permitted then the speclca-
tons in this regard must be delayed until the
called for them be delivered and the density of
each sample obtained do not know which TO
admire most. the ingenious adms ION thai am right,
or the refreshing innocence with which Colonel Paine
attempts to cover up that admission. All that have
ever conended Tor that the density OF the steel
not DO taken INTO consideration uA the kind OF steel
to be used is decided upon THIS is made very appa-
from the report OF The Chief Engineer who says
page II, Under the speoin would proc.
nby have to deal with every variety OF steel from the
light carbon STEEL with one and half per cent or
more Of carbon, down to Bcsscmcr containing often
less than onc.quarer per cent, aud from that to the
still heavier chrome STEEL
DENSITY GAUGE WIRE
"Now,' said Mr.. Ill., ~ have admitted that the
gincer has perfect right to assume certain density
tho gauge OF his and hence the OF his cables
HIS report seems TO admit this by saying:-'Now #
the material which the contractor uses should prove
lighter than the hgure fixed above t4S4 pounds) he
will be Obliged TO slightly increase the diameter of his
wire in order 10 make IL weigh fourteen feet to the
pound II his material Is heavier the reverse will be
tho case But Colonel Paine, on the other hand,
fixes the diameter OF tho wire at l6e,
having stated the size full We have
here very plainly the two horns OF the dilemma with
Colonel Paine clnglng and the Chiel Engineer
suspended from the other If Colonel Paine viii take
the trouble to ascertain the cubic contents OF wire Of
his diameter, fourteen feet long and weighing one
pound, he will discover by continuing the process
that cubic foot thereof Weighs 467 pounds and not
4Ss pounds, as demanded in the specifications"
"You have also attacked II remember rightly, the
consistency between the gwen modulus OF elasticity
and the least total stretch within the elastic limit
Paine say to this?n
"In his reply said Mr.. Hin, .'Cooncl Paine has
taken advantage ofa typographical error made by the
HERALD which confess was not fully corrected
on the following day. Alter having made this typo
graphical error bear the burden OF his argument,
Colonel PaInc contlnucs:'By taking 20 900 600 the
modulus and using the formula referred to- the results
exactly correspond with given in the specinca-
tons, as FAR as they carried out decimay, which
Is far enough tor al! practical purposes
MISTAKEN CALCULATION.
I'll Colonel Paine will use this modulus Of 30 0O0 900
and also 1000 pounds ais elastic limit he need
carry the decimal result very far before he
will ind that the least stretch equal 26O OOO
and not 1914 100 0OJ Of the 30 feet" stated In tho
specifications. Perhaps he will also ind that stretch
OF 194-l00 900 corresponds to elastic limit of
1,200 and not OF 600 pounds Hero again we find
Colonel Paine riding the modulus, while the engineer
maintains tho elastic limit For the latter says In his
rcport-As long as am sure OF an elastic limit OF
1000 pounds, and that the maxim strain OF each
wire In the cable will be about $40 pounds, abso-
lutely sale beyond all contingencies, II every
wire were to treak with g. 900 pounds strength
''Leaving aside all further argument on ultimate
strength and the positive necessity OF adherng TO his
co-clhcient oil safety in so important structure, 1
really la to sec how IL is possible for the engineer
have elastic limit of 47-l00 OF the ultimate
strength, have his wire break under strain OF 1000
pounds, aud still bo sure OF elastic limit OF 1000
pounds"
''what Mr. HILL would be tho practical result Of
those Inconsistencies and in the specifications p?
"ln the contract were to be awarded these
specifications difficulties would arise-1rst the i'm
possibility OF procuring the material that woad guar
antec the pcrmanency OF the structure and next
facility with which a contractor desiring to break his
with the trustees could involve the tax paw.
OF the TWO cities in tedious and expensive ga-
ton, in which they would almost certainly be do
Il atoh