Abstract: A ladder anchoring system for ladders with hollow bore ladder rungs, which includes: first and second vertical shafts each having a hollow bore disposed between opposite open ends; first and second elongated ladder securing members dimensioned to respectively slideably fit through the hollow bores of the first and second vertical shafts; and first and second horizontal members. The first and second horizontal members are attached in parallel and between the first and second vertical shafts. At least one of the first and second vertical shafts is detachable from the first and second horizontal members. An attachment means is provided for reversibly securing the first and second horizontal members to at least one of the first and second vertical shafts.

Abstract: An electrical power system is provided for supplying DC power to electrically motorized vehicles, emergency standby sources, and the like wherein a lead-oxygen battery cell used as a source of DC power includes a positive charging grid, a conventional negative electrode, a positive discharging electrode, and a teflon membrane member coated with a catalyst contained in an atmosphere of oxygen which is admitted to the cell through the teflon membrane. Oxygen is given off during the charging cycle and is compressed in a storage tank for re-use during each duty cycle providing a closed system wherein contamination is minimized and a long-life cycle can result.