Photo-electric Colorimeter
Photo-electric Colorimeter, consisting of a lamp, a cuvette holder, a blocking screw, a filter and a photo-electric cell in alignment, by Gallenkamp, 1900-1980
Photo-electric Colorimeter with a voltage transformer. The colorimeter consisting of a lamp, a cuvette holder, a blocking screw, a filter and a photo-electric cell in alignment
Photo-electric Colorimeter, consisting of a lamp, a cuvette holder, a blocking screw, a filter and a photo-electric cell in alignment, by Gallenkamp, 1900-1980
Voltage transformer for Photo-electric Colorimeter, by Gallenkamp, 1900-1980