Produced for the Flickr "Macro Mondays" challenge. This is part of a limelight. The curved tube and nozzle on the LHS produces an intense narrow jet of oxy-acetylene flame directed at the central spigot at the top, on which is mounted a cylinder of lime. The lime is heated to white heat and gives off copious amounts of light, which is focussed and directed by a mirrored housing down onto the stage. The bevel cogwheels rotate the central shaft whilst at the same time raising the cylinder of lime in relation to the flame, thus exposing a continuous fresh surface in a spiral, in order to give a consistent output. The business end by John Liddle, on Flickr
