Chicago : Engineering and Contracting Pub. Co. · leaf 333
TIMBERING OF ARCHES IN WESTERLY APPROACH. TIMBERING FROM STATION 185 + 43 TO STATION 186 + 21. … TIMBERING DETROIT APPROACH BETWcEN STA. 158 I 00 ANO 158 + 75 SHIELD DRIFT SECTION AT STATION 158 175 LOOKING EAST. Fig. 2—Sections Showing Methods of Drifting and Tunneling. I tractive methods alone and to tunnelingproper, excluding open cut excavation. I Ik .<• Iioir of III. we t< jlv…
Buildings
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