Science Frontiers ONLINE No. 105: May-Jun 1996 | |
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We hardly need more than the accompanying drawing to amplify our brief item (in SF#103) on that remarkable 7th. Century Mayan suspension bridge at Yaxchilan, in Mexico. Its three spans stretched 600 feet. The wooden deck was 10 feet wide and was suspended by large-diameter hemp ropes - probably bundles of six 1-inch ropes, according to modern calculations. The towers of the two bridge piers were 35 feet across and built up from large, flat stones (4 x 4 feet) set in bedrock. European engineers did not build a larger bridge until 1377! The following reference contains much more information.
(O'Kon, James A.; "Bridge to the Past," Civil Engineering, p. 62, January 1995. Cr. S. Jones)
The precocious Mayan suspension bridge at Yaxchilan. Temples and other city buildings in background. |