Faraday induced the mechanochemical reduction of AgCl with Zn, Sn, Fe and Cu in 1820, using trituration in a mortar. This
experiment is revisited, employing a mortar-and-pestle and a ball mill as mechanochemical reactors. The reaction kinetics
depends both on the thermochemical properties and the hardness of the reactants. When using Zn as the reducing agent, Faraday
likely observed a mechanically induced self-sustaining process (MSR), or at least he came very close to doing so.