Abstract: A vertically reciprocatible heddle frame has side beams including a heddle bar fixed to the side beams, and heddles loosely mounted on the heddle bar with vertical play. A device for detecting end breakage of yarn supported by the heddles consists of an electrically conductive bar mounted on a resilient holding element. The resilient holding element leaves access at the top for contact between the heddles and the detecting bar. An electrical current flows through the detecting bar only during the downward movement of the heddle frame. End breakage of yarn permits a heddle to contact the detecting bar during such downward motion, and the resulting completed electrical circuit can be detected by appropriate detecting means.