Chicago : Engineering and Contracting Pub. Co. · leaf 665
sults of such investigations are avail-able it would be well, we think, to postponelegislation providing for actual reclamation. EARTH AND ROCK SECTION Portable Rock Drills for Trench Work. Havana Sewers. On the construction of sewers in Havanaa large amount of rock excavation has beennecessary in… … Fig. 1.—View of Portable Drill Rig forHavana Sewers. No.holes. Drill No. 1, total 6 Average per ft Drill No. 2, total 6 Average per ft Drill No. 3, total 10 Average per ft Drill No. 4. total IS Average per ft intermingled with rock as hard as flint; muchof it breaks up like slag, while some is…
Buildings
Internet Archive · University of Illinois Urbana-Champaign · Public Domain Mark 1.0. Free to use for anything.
