A test used to detect a suppressed strabismus (squint) in children. The child is asked to look fixedly at an object with one eye while the other is kept open but covered by the hand of the observer. The hand is then withdrawn: if the eye that had been covered is seen to move toward the nose to adjust to the focus of the uncovered eye the child is assumed to have a divergent squint; movement of the eye away from the nose implies a convergent squint.