The Houston daily post. [volume] (Houston, Tex.) 1886-1903, 1901-07-07
AMERICAN eRIpeE-RulLpeRs.
Excepting Canada, They Are Twenty
Years in Advance Of Other Nations.
Engineering Magazine

Excepting Canada, They Are Twenty
Years in Advance OF Other Nations.
Engineering Magazine
Americans are twenty years In advance of
other nations Except Canada in the art of
bridge design and construction. The steel
Of which a bridge Is made represents about
half of its cost. Steel is now made In the
United states az much less cost than in any
other country In Britain labor Is so much
hampered by trades-unlonlsm that It is ad-
mltted by one of the leaders that the cost
of labor in milking steel in the United
States Is NOT one half of what il is in
Britain. This can be said also of the labor
employed In manufacturing,
The market for bridges Is far greater in
the United States than elsewhere The
states have now 100000 miles Of RAILWAYS.
and II has been estimated that there is nn
average of one span Of metallic bridge for
every three miiec Of railway. This gives
b3OOO bridges on existing lines. without
including those required for new lines. The
Increase 10 the United States of the weight
OF cars and engines has resulted in Won
derlul economic changes. The average rate
OF trcightS on American railways was in
1861 little over 81 per ton. Now 1t aver.
ages 20 cents Any one can figure the
saving on ifHoM.0OO tons Of freight moved
In 1900. These larger cars carry double
the paying load of the old ones that they
nave superseded, and more powerful en-
II.
crease ot weight Of rolling stock has led
10 the renewal Of the 63.O0O old bridges by
stronger and heavier ones. This demand
has brought into existence many bridge
building companies, and they can well af-
ford 20 equip themselves with the best
labor saving and accurate working ma
emuery, resardless Of first cost As they
know IL would seldom II ever lie idle. Eu-
ropeun bridge builders are not in this posi-
non. Trains dave not increased in weight
as they have in America The old bridges
mn nd ha lsaf7t "a
hcen chiefly confined 10 new ones. Bridge
building is merely an adjunct TO other
business, and possibly the owners are wise
tools
The American bridge engineer of today
has few OF the difficulties that were over.
The mathematics OF simple forms Of
bridges was understood in 1870, hut tho
proporuoning OF details hAd to be worked
out by each man for himBf Every new
span WAS a new problem Now. tho pro
portions OF lengths OF span to height, and
me lensih OF panels. have been fixed by
p,aCa,Seii Ipnnecuons have become so far
standardized that the duplication Of parts
can be carried 10 IT'S fullest extent The
proper spacing Of rivers is now better
uthilerStood. Designs are so made thai ma
tutne Tools can make every part Great
accuracy is attained and the sizes OF parts
naye increased The bridge Is never as.
seinoled 9nth II reaches the staging or
islse works. and u comes together like
the parts Of clock. Much OF It is fas.
tened together by power rivetters. Rxcept
IN q rev Instances, the American bridge
builders know that the designs OF the en-.
queer Or the purchaser will be similar 10
nose mat he has been In the habit of
N9,kiug under and no abnormal features
VIII he embodied. Everybody now knows
Nn9l every one else Is doing The foreign
engineer, with some notable exceptions. Is
soineWhat Isolated IN his own ofhce. and
sol{es each problem by requiring strength
anu anu uurablllty only, and without much M
lehNoh 10 me use OF such details as insure
e eSol.,y OF construction and rapidly OF