New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1880-03-28

Lake Shore Railroad Company tor damages Oh
account of injuries received at the Asltahula
accident much scientific aud practical testl-
m0ny of the highest character was gwen IN
relation to the construction OF the bridge and
tie ties applied 10 IT, showing that the Howe
truss plan used in the structure combines the
most perfect and direct method OF applying The
mower of material that the Factor of safety or
strength Of the bridge WAS three times rs great
as the load upon it at the time Of The accident;
that examinations had been made with two
heavily loaded freight trains standing upon the
bridge, and that the DETECTION was less than
the standard allowed-one-twcly c-hundredth
Part Of the length of the span aud that no
doubt was ever entertained up to the time Of
the accident as to the strength and sulliciency
of the structure.
Why, then, did the bridge give way7 This
question is answered IN letter recently written
10 Mr. Stone by General b. 4. Morton, a distn
guished civil enyineer Of Nrw-Haven, Conn.
Al the time the Ashtabula bridge was built,
saws General Morton, the science of bridge
building was in It's infancy, and it has scarcely
yet reached youthful stage The action Of
wind upon bridges was but little understood,
and was not taken into consideration to the eX-
tent of providing against its power. The
valley of Ashtabula Creek from the bridge TO
the lake has the shape of a double funnel,
through which two currents Of air are coucen
trated upon the bridge. A stiG gale WAS blow
ing up the valley ut the time of the accident, OK
erting force latcIally ar the point Of contact
with the bridge Of $4,000 pounds, according TO
General MOrtOn's estimate. AT the same time,
he thinks, an upper current of wind from the
northwest having n velocity of sixty miles an
hour, srucll the train at an angle of forty-fve
deg eCs. The speed of tie train WIS fifteen
miles an hour, and the resistance is calculated
nj twcuty-threc pounds TO the square foot.
With this force to be overcome by traction
upon the rails, and with the tremendous pres
sure Of the lateral current upon the bridge,
there was q STRAIN upon II which no human fore
sight could foretcl General horton antici-
pates the question, RI it was the wind, Why
didn't the bridge blow down bcro.c} and re-
plies: When we see the sturdy oak that has
"withstood the wind. and storms Of a thousand
"vintefa suddenly plosuated to tie earth, We
"cxclaim, why did il not bow down before 2
Simply because tornado had not previously
"cross.d rs track. If We need more evidence
"of the destructive force OF are WIND, ! nave
but TO call attention to the destruction of The
"Omaha bridge, the destruction of the village Of
WalHngford, aud Of the Tay bridge
The Asltabula qud Tay disasters have shown
that bridges exposed 10 powerful wi1d-acton
must, if possible, BE- made suoug enough to
support the weight of heavy Trains plus do
greatest pressure of air taat ia likely to be
brought 20 bear upon them. Engineering skin
viii no doubt be devoted TO the solution OF
tins problem. Tat 1t did not receive atten-
tou years AGO WIS nobadv5 fault, because cx-
pehcnce did not show until recently iiat ,here
was aay reason 90 opirhcrd destructive con-
sequence fom Che pressarc OF wind on tho
strong open hoa truss work OF railway bridges,
or even upon this truss-wo.s plus the almost
solid wall offered by The side Of the moving
train.