.FIG. 13 is another plan view of the gripper of FIG. 12;FIG. 13a is a detailed view of the structural relationship between the cam surfaces 144, 146 and the gripper arms 122 and 124 in a second extended position.FIG. 14 is a perspective view of a picker mechanism for use in the data storage library of FIG. 2, showing a first side thereof; andFIG. 15 is a perspective view of the picker mechanism of