. Official proceedings . I/,-°BaisirCenlefs(Vertical) l/j-°Bars 12Centers 85 Rails l/,°Bars 12 Centers(InclinaJ) X Bars 9Centers asRail Anchors SRails 85* —\24-6 I—Center ol Gravity ol Obelisk ?.»t 30-r°Bars7270 • 20 U-Bolts a 14150. OM Rails 23-0Long2-6 Centers with r° Bars20Long through Webs Note: All Pipes IV; Diameter,Pipes B i C Staggered ,16 Pipes3 ConCenters -Rows of K* Bais ELEVATION LOOKIMGUPSTREAM SECTION THROUGH OBELISK PEDESTAL FIG. 4.—Sections Through and Accomplishing the Fall ity of about 20 ft. per sec. On the west side of the main chan-nel was
. Official proceedings . I/,-°BaisirCenlefs(Vertical) l/j-°Bars 12Centers 85 Rails l/,°Bars 12 Centers(InclinaJ) X Bars 9Centers asRail Anchors SRails 85* —\24-6 I—Center ol Gravity ol Obelisk ?.»t 30-r°Bars7270 • 20 U-Bolts a 14150. OM Rails 23-0Long2-6 Centers with r° Bars20Long through Webs Note: All Pipes IV; Diameter,Pipes B i C Staggered ,16 Pipes3 ConCenters -Rows of K* Bais ELEVATION LOOKIMGUPSTREAM SECTION THROUGH OBELISK PEDESTAL FIG. 4.—Sections Through and Accomplishing the Fall ity of about 20 ft. per sec. On the west side of the main chan-nel was a projection of bedrock which formed an island atextreme low water. The ordinary crib cofferdam structurecould be carried across the shallow part of the river to thisisland, but no further. It was therefore chosen as the properspot on which to build the obelisk. A Concrete Water PlugAccurate determination of the topography of the river bedin the main channel was, therefore, a necessity. It was accom-plished by taking soundings with a 1,000-lb. cast-iron ball, sms- 179 pended from a cableway, and operated by a hoisting engine,the cableway being shifted up- and downstream so that thedesired area could be thoroughly covered. As these measu
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Keywords: ., bookcentury1900, bookdecade1900, bookidofficialproc, bookyear1901
