Photometer
Chamber's Etymological of the English Language · 1895 · p. 386
fo-tom’et-er, n. an instrument for measuring the intensity of light. [Gr. phos, phPtos, light, tnerron, a measure.] Photophone, fo'to-fon, «. an apparatus for transmitting articulate speech to a distance along a beam of light [Gr. phds, phdtos light, and phone, >ound.]
Readham'da tam maddeyi gor →