Abstract: A method of plugging wells wherein cementitious materials (like Portland cement) are formed into pellets that can be dumped or dropped into a well that is filled with an aqueous solution. The pellets will fall quickly to the bottom of the well or mechanically placed barrier, and over time, the pellets will loose their structure and release dry cementitious material into aqueous well fluid. The cementitious material will wet in the aqueous well fluid and then set to form an impermeable plug in the well.

Abstract: An energy converting exercise device comprising a housing and a shaft extending therethrough for frictionally resisted axial movement of the shaft relative to the housing. The housing includes adjustable braking means to allow the user to vary the level of resistance to such relative axial movement, and operatively associated with the shaft are readout means to indicate to the user in units of applied force the instantaneous level of resistance effective as he moves the shaft axially relative to the housing.