 Another kind of classical mechanical supertask was described by Pérez Laraudogoita (1997). Consider again the infinite lattice of particles of the same mass, but this time suppose that the first particle is motionless, that the second particle is headed towards the first with some velocity, and that the velocity of each successive particle doubles (Figure 1.4.2). The first collision sets the first particle in motion. But a later collision then sets it moving faster, and a later collision even faster, and so on.