Gear Lock

I scrambled up the radiator ribs straight onto the sunny living room windowsill. Right in the middle sat the heavy white latch of the double-hung sash window. The curved cam lever was pivoted open, exposing a solid brass gear plate tucked beneath the housing! I braced my blocky boots against the painted sill, gripped the grooved metal arm with both hands, and hauled it forward with all my weight. Click-clack! The rotating cam swept smoothly into the catch, drawing the twin sash frames flush against each other with zero rattle. Heavy-duty window security locked down!