Check Rail: The bottom rail of the top sash and the top rail of the bottom sash of a double hung window that meet horizontally in the center of the unit or the two vertical members of sash in a slider window that meet in the center. This is also sometimes called the meeting rail.
Did you know: Robert Hooke, the 17th century inventor of the double hung window was also the architect who rebuilt the famous London mental hospital, Bedlam (aka the Bethlehem Hospital, Moorfields) after the Great Fire of London?
Bedlam is Europe’s oldest extant psychiatric hospital and has operated as such, continuously, for over six hundred years. Hooke kept offices in the central cupola of the hospital until his death.