On Colour-Blindness extracted from Philosophical Transactions of the Royal Society of London, Volume CXLIX (49), Received March 24, Read April 7, 1859, pp. 323-339

London: Taylor and Francis, 1859. 1st Edition. First edition, disbound, near fine extract of "the first full and reliable account of the state of vision in red-green blindness" (Report of the Annual Meeting, Volume 62, p. 735). Today Pole's work is considered to exhibit "highly ingenious reason"; at the time it was largely ignored (Ladd-Franklin, Colour and Colour Theories, p. 192). Includes large diagrams of Chevreul's Colour-Circle.

William Pole's paper resulted from self-study as his vision was dichromic, meaning that his two color sensations were yellow and blue and that the red, orange, and green parts of the spectrum appear to him as varying shades of yellow. "Greenish-blue and violet appear blue, and between the yellow and blue portions of the spectrum... there is a colourless grey band in the position of the full green of the ordinary spectrum (RAM, p. 735).

Pole notes that this neutral band is seen in the spectrum in "all cases of dichromic vision. It may appear white or grey according to the intensity of the light, and it apparently results from an equilibrium of the two sensations: no such band is seen in the spectrum by a normal eye. Mr. Pole... considered it impossible to explain his dichromic vision on the commonly received theory that his sense of red is alone defective and that his sense of yellow is a compound of blue and green.

[Pole] believed his green quite as defective as his red sensation and that yellow and blue are quite as much entitled to be considered fundamental sensations as red and green. He suggested that in normal colour vision there are at least four primary sensations - red and green, yellow and blue" (ibid). CONDITION & DETAILS: London: Taylor and Francis. Extracted from The Philosophical Transactions. 4to. 11.25 x 9; 281 x 225mm. Pp. 323-339. Near fine condition. Bright and very clean.