{HEAD ~ A folding stairway} interconnected with {TAIL ~ a basement window} and its lock, for unlocking the window and opening the window when the stairs are pivoted from a closed or folded position to a down, usable position 
interconnected with
{ HEAD ~ A folding stairway } interconnected with { TAIL ~ a basement window } and its lock , for unlocking the window and opening the window when the stairs are pivoted from a closed or folded position to a down , usable position
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH