Geomag Mechanics Loops and Turns 130 Piece Construction Set £34.99 from The Entertainer. Mechanics Gravity Magnetic Track harnesses the invisible forces of magnetism and gravity through original and surprising means. The spheres inside the circuit are set in motion by an innovative magnetic cannon that uses the force of attraction of the accelerating magnet. Gravity is the innovative evolution of the Geomag Mechanics line. Developed with expert players in mind, the new construction system is based on an innovative “gravity motor”: this uses the weight of the Geomag spheres to kickstart the mechanisms and movements of the Geomag Mechanics structures. The motion is provided by the invisible forces of Gravity and Magnetism, without using electricity or batteries. The play experience is based on these fundamental principles of physics. Mechanics Gravity is a STEM product that can truly stimulate curiosity and inspire to learn more about science.