Chicago : Engineering and Contracting Pub. Co. · leaf 1285
oller bearing carriage. Locks automatically in any desired digging position, releasesautomatically and travels along the boom to the end to dumpingposition and dumps automatically. Excavates below derrick base to depth within the lengthof dipper arm and weight of boom can be used to aid indigging,…
Buildings
Internet Archive · University of Illinois Urbana-Champaign · Public Domain Mark 1.0. Free to use for anything.
