Used for the accurate clinical determination of haemoglobin and other blood constituents. Wooden box. This absolutely first-class manual photometer appeared around 1950, and was the culmination of a decade's work, led by Professor Earl J King at the Hammersmith (in the meantime he had encouraged many hospital Biochemistry labs to make their own simple photoelectric colorimeters, with major benefits to the quality of their clinical services). The MRC particularly recommended this photometer for blood haemoglobin measurement, using a simple oxyhaemoglobin procedure to give very accurate and precise results, which remained the standard until superseded by automated cyanmethaemoglobin methods in the late 1960's. This particular instrument probably dates from about 1960, and was last overhauled by the makers in 1967. It was used in the hospital group which then encircled Cambridge, and was used latterly by the Pathologist Dr John Dean (later Histopathologist, retiring in 1980) in Saffron Walden Hospital Path Lab. for measurement of patients' blood urea's and blood glucoses there