Improvements in or relating to the simultaneous recording or reproduction of sounds and moving pictures
GB332567A
Improvements in or relating to the modulation of a beam of light, for use for example in the recording of sound or in the reproduction of recorded sound
GB325594A
Improved means and method of illumination for taking and projecting colour photographs
GB324673A
Improvements in apparatus for sound recording and reproduction
GB324674A
Improvements in apparatus for sound recording and reproduction
GB324101A
Improvements in or relating to luminous vacuum tube devices
GB323564A
Improvements in or relating to mercury vapour lamps
GB289326A
Improvements in or relating to vacuum tube illuminating devices
GB286052A
Improvements in or relating to colour screens for photographic purposes
GB214274A
Improvements in apparatus for recording and reproducing sound
GB237942A
Improvements in or relating to vacuum tube illuminating devices
