Maxwell's Top is designed to illustrate gyroscopic precession. The apparatus consists of a wooden top with an attached adjustable spindle which rests on a support rod mounted on a tripod. When the spindle is adjusted so that the pivot is above the center of gravity, the top will precess in one direction. When the pivot is below the center of gravity, the top will precess in the opposite direction. If the pivot is set so that it is coincident with the center of gravity, the top will not precess at all, but spin steadily about the axis on which it started. If the pivot is set coincident with the center of gravity and the top spun with the axis vertical, it will move along any object held against the top of the spindle. If the fingers are held against the upper section of the spindle, it will follow the contours of the spread fingers. This "contour following" is another application of precession principles. As the spindle touches any object, it tends to roll; but this rolling produces a precessional torque at right angles to the direction of rolling thus increasing the pressure between spindle and object.