4D CONTROLLED TRAJECTORIES (3 CONSECUTIVE FRAMES) There is an increasing interest in the chemical community in under- standing not just the static structure of chemicals, but the ways in which they move and vibrate. Currently, the large volume of data being generated makes it very difficult to interpret. The Graphics group has generated a number of tools to provide the chemist with a variety of representations of a moving molecule. The data being demonstrated are avian-Pancreatic-Polypeptide (aPP) which have been loaded into a relational data base. When the animation is being run, the user may control the angle of view with the 3D-joystick, the scale and panning with the tablet, and the speed and direction of motion with program function keys. The demonstration shows three consecutive frames during molecular motion. These frames may be superimposed using the tablet so that the changing orientation of the molecule may be seen. This helps a chemist analyse molecular motion.