(under subclass 242.1) Conduit wall structure wherein the conduit wall is formed of a hardened clay or powdered alumina, silica, lime, iron oxide and magnesia material used in; e.g., water wells.
SEE OR SEARCH CLASS
52, Static Structures (e.g., Buildings),
19+, and 169.1+, for a masonry construction, per se, surrounding an open space which may be defined as forming a cistern or well.
405, Hydraulic and Earth Engineering,
132+, for tunnel structure and structure of shafts of general utility; and subclasses 231+ for columnar foundation structures (e.g., pier, pile) and methods and apparatus for installing the same.
