The props for the lectures are designed and created by the RI's science demonstration technician, a post which Faraday previously held. A popular technician, with the advent of television, serving from 1948 to 1986, was Bill Coates. The technician is informed of the general subject of the lectures during spring, but the specifics aren't settled until September, with the recordings made in mid-December.[1] By 2009, the lectures had expanded to a series of five sessions each year.