art, political structures and scholarship
that would be distinct and original
rather than merely copying European
culture and taste.
In modern engineering terms, these
doubts center on the difference be-
tween labor and materials. Labor
being cheaper in Europe means that
material savings dominate design
ideas, whereas materials being cheaper
in America, labor savings are sup-
posed to dominate design ideas in the
United States.
We need to look critically at these
clichés today. They reflect in part a
questionably conservative attitude to-
ward design and a justifiably cautious
attitude toward building.
The Walnut Lane Bridge raised
again this question of labor and mate-
rials and it was criticized for being too
much a European design. Magnel had
made the design through the Preload
Corporation whose vice president Cur-
zon Dobell reported that “it took 152
man-hours to assemble and install one
ton of prestressing wire” for the
bridge.
35
Magnel himself was astounded at
the problems associated with getting
American industry to manufacture
special fittings. He used to lament that
all would have been well, if instead of
twenty end cable fittings, he could
have ordered one million!
Admiral Jelley, Chief of the Bureau
of Yards and Docks, perhaps summa-
rized best this viewpoint in his “Clos-
ing Summary” to the MIT Conference:
“We have seen American adapta-
tions of European practice in bridge
construction. The Walnut Lane Bridge
in particular was a direct application
of Dr. Magnel’s system.
“However, the Arroyo Seco pedes-
trian bridge (California’s first pre-
stressed concrete bridge) had an inter-
esting departure from European
precedents – a button type of anchor-
age was used. I think that this is sig-
nificant because I consider that Euro-
pean ideas should not be copied
blindly. Construction conditions in
this country, particularly trade prac-
tices, preclude this. American engi-
neers must find and develop their own
solutions.”