An apparatus for finely actuating a glass electrode or the like tool includes a movable portion adapted to be vertically displaced with the aid of a vertical actuating mechanism. A Y-coordinate slider is mounted on the movable portion to slide in the Y-coordinate direction and a X-cordinate slider is in turn mounted on the Y-coordinate slider to slide in the X-coordinate direction. A Y-coordinate thrusting rod is provided in the movable portion to thrust a Y-coordinate lever rod disposed between the Y-coordinate thrusting rod and the Y-coordinate slider, while a X-coordinate thrusting rod is likewise provided in the movable portion to thrust a X-coordinate lever rod disposed between the X-coordinate thrusting rod and the Y-coordinate slider. This enables a lever ratio to be reduced to a fraction of the ratio. Two return springs are provided so as to allow both the Y-coordinate slider and X-coordinate slider to resume their original position. One of them is resiliently bridged between the movable portion and the Y-coordinate slider and the other one is resiliently bridged between the Y-coordinate slider and the X-coordinate slider.
