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Show " United States. 1 The glued laminated wooden, ai ches In bridge construction ha a number of advantages. The ar ches can be factory built in pleas ing shapes and sizes impossibli to attain in solid timbers, anc from pieces of such dimensions that they have little structural value except when bonded togeth-1 togeth-1 er with glue. The boirds or strips from which the arches are built are more easily obtained than solid timbers, are more easily sea- soned, and more conveniently shipped. Up to 60 percent of low-grade low-grade boards or strips can be used m the central part of each arch I a significant fact in view of the large areas of second-growth fo--ests on which .tills country is becoming be-coming increasingly dependent S !I 1 thiS type of- cwatruc- as it, eX'PeCted to incase as its merits and possibilities be come better known. o Uued Wood ; o Arches Span j d Wisconsin River ' I 6 tt TuB, &St bridge evei built In the f I r Ked States using glued laS-1 j r mated arches, for supports now ' spans a river at Madison, Wis the ; home of the U.S. Forest Product : boratory. The construction of by the development of glues which afford bhighly water-res4nt jTs ' The bridge, which is for pedestrians, pedes-trians, was built by the J J entirely of wood, and was seltd in competition with various ma- Two arches, 73 feet 6 Inches ' I only 8 wches widemreeS ed to span the river. They look I le solid timber arches h,l I I -ally buut from J giued together After , were in i the arches were m place, a walk was nailed of a iarp T th consti-uction orS Ttw"6 designs havTbln Ted |