Remarks on the examination and classification of cases of colour-blindness (1879)
Berry, George Andreas, 1853-, Tweedy, John, 1849-1924, former owner, Royal College of Surgeons of England · Edinburgh : Oliver and Boyd · leaf 8
of the green, and a weak excitation of the two others ; and blue, by a moderately powerful excitation of the green and violet elements, and a weak excitation of the red. This is represented diagram- matically in the accompanying figure taken from Helmholtz, where the colours of the spectrum are… … Fig. 1. (After Helmholtz.) As we shall elsewhere consider in detail the arguments for and against the Young-Helmholtz theory, we have at present merely to state that, although its supporters imagine that they see in colour- blindness the strongest arguments in its favour, we doubt whether it or any…
Color Vision Defects
Internet Archive · Royal College of Surgeons of England · Public domain (published before 1931). Free to use for anything.
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