Four pads of pseudoisochromatic plates record sheets (second edition) by American Optical Company 1957
'Colour Test 55': black, wooden box with 3 coloured cards, crudely made, perhaps for testing for differences in binocular sensitivity to colour, 1940-1955. (BPS Inv. No. 0153) 'Colour Test 55': black 1940-1955
A test for defective colour vision, electromechanical counter in 'home-made' wooden box, 1955-1975. (BPS Inv. No. 0073) A test for defective colour vision 1955-1975