Illuminating Engineering Society, Association of Public Lighting Engineers (Great Britain) · [London] · leaf 136
g to note how closely thesephotographic results confirmed the resultsexpressed in Captain Strouds actualphotometric tests. The design of the Holophane lens wasof an interesting nature. There were aseries of bulls-eye prisms in the centre tocontrol the central rays. At the sidesthere were prisms to… … Ordinary parabolicbeam. Ordinary beam transmitted through Holophane lens. Fig. The Chairman* (Lt.-Col. F. A. CortezLeigh), who explained that he wasunavoidably called away at this .stage ofthe proceedings, expressed his apprecia-tion of Mr. Walshs paper, and of thecontributions of various speakers.…
Lighting
Internet Archive · University of Toronto Libraries · Public Domain Mark 1.0. Free to use for anything.
