Morning journal and courier., 1880-07-21
CHARLES J. COLE, Hartford. June 25. 1880.

THE FAY BRIDGE-WIND PRESSURE. The report on the Tay bridge disaster l made by Mir. Rothesay, Wreck Commissioner 1 of the Board of Trade, is refreshing reading
 in this country, where so many people are
 killed or wounded while travelling. and mo- body is found to blame or censure is so
 vague as to affect no one in particular. MT. Rothesay does not deal in whitewash, but
 holds a number of persons responsible by
 name. The distinguished civil engineer Sir
 Thomas Bouch, who designed and supervised
 the construction of the bridge, is chiefly
 blamed for the horrible casualty. MT. Rothe-
 say declares that the bridge twas badly de-
 signed, badly constructed and badly main
 tained, and that it's downfall was due to in. herent defects in the structure which must
 sooner or later have brought it down. He
 says that ''for these defects in the design
 the construction and the maintenance Sir
 Thomas Bouch is, in my opinion, mainly to
 blame. For the faults of design he is entire ly responsible" " So much for Sir Thomas
 The contractors, Hopkins, Gilkes & Co.,, are next taken in hand, and the finding is that this firm allowed grave irregularities to go on unchecked and unrebuked in the course of the work. They did not appoint competent persons to superintend it's details. Their great object was to rush through the job and get their money. The railroad company also comes in for share of the censure. It should not have permitted trains to be run through the high girders at a speed greatly in excess of the rate Twenty-Five miles an hour) 1aI~ La5
 treme limit of safety by General Hutchinson
 @ Board of Trade inspector. The great Board of Trade itself is not excepted from this fearless criticism. It is shown that the in spection made under it's auspices was super feial and included no allowance for wind pressure, which was quite serious omission in view of the fact that the wind blew down the bridge or, rather, was the most immediate and powerful cause of its fall
 It is encouraging to see how faithfully and fearlessly Mir. Rothesay has done his duty, and it is also encouraging that the disaster has directed much attention to a matter con- corning which there does not seem to be very definite knowledge, namely, wind pressure on bridges and other structures. The testi- mony given at the Tay bridge inquiry showed an astonishing divergence of opinion among meteorologists and engineers in regard to the force of the wind Sir George Airy, As tronomer Royal, testified that the maximum pressure recorded at Greenwich was forty pounds per square foot, and he thought it likely that, had not the instrument given way, fifty pounds would have been reached At limited times and over limited surfaces the pressure might range between fifty and one hundred pounds in a valley like that of the Fay; but over such large surfaces that presented by the fallen bridge the pressure would be very much less. For the Firth bridge he had estimated ten pounds per square foot, but thought that in the case of a structure built and located like the Fay the figure ought to be higher. Prof. Stokes and Robert H. Scott, of the Meteorological office, took exception to this estimate, which they considered too low. From Mir. Stokes evi- dence it appears that at present scientists have succeeded only in attaining an approx 1 imation in calculations on the pressure of wind on plates. MT. Benjamin Baker. an engineer, stated that in his opinion the lat eral pressure on the bridge did not exceed l fifteen pounds per foot, and thought it was idle to talk of pressure of forty pounds per | foot 1
 Our present knowledge, as will be discov- | cred from the above, does not even | define the maximum amount of wind pressure l to be guarded against in bridges and other | structures but it is not likely | that we shall remain so ignorant much longer, l for experiments are now in progress, or are | soon to be made by our Signal Bureau and | others, which will throw light on this impor- tant matter. Until engineers know more about wind pressure they must, if they wish | to have their structures safe, adopt the plan used at the St. Louis bridge of considering latticed work equal to close wall