Benjamin Franklin's enunciation of his so-called ‘one-fluid’ theory of electricity in the period 1747–55 nas often been hailed as an important milestone in the history of physics. So indeed it was, for, with the rapid and widespread acceptance of the new theory, the science of electricity became based for the first time on the view that the electrification of a body involved the accumulation of a ‘charge’ from elsewhere, rather than the excitation of matter already present in the body. Only (...) a little more remotely, the triumph of Franklin's theory over the rival ‘excitation’ theory espoused by the Abbé Nollet paved the way for the more sophisticated fluid theories propounded by Aepinus, Cavendish, and Coulomb in the years that followed. (shrink)