ABSTRACT
Many other kinds of hard particles (sand, powder, pebbles) of less regular size and shape, are even less likely to find an ordered state. So the disordered packing of spheres can stand as the prototype for a wide class of important granular materials. It is worth pursuing with some precision. We do not have to go all the way with Cyril Stanley Smith, for whom ordered states were “dead” and disordered ones “alive,” to appreciate their importance.
