Spectrochemical computer analysis - instrumentation

A microphotometer is described for making magnetic tape recordings of spectra 480 mm long from 102- by 508-mm photographic plates. Transmission readings are recorded at a rate exceeding 1,300 per second for every 5.08 um of length of the spectrum, A two-line
cadmium fiducial line system and a developing tank for 102- by 508-mm plates also are described as equipment ancillary to a system of
computer spectral analysis applied to the spectrochemical analysis of geologic materials.