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 20
are not so far distant as to be complementary, the whiter is the mixture, although always mid- way between. As we cannot receive the sensation of purple from a homogeneous impression, the mixtures giving rise to the re- sultant molecular movement must, according to the figure, produce more whitish,… … Fig. 3. If, now, we imagine the rotatory molecular movement rendered impossible in any one direction represented by any of the diameters in the figure, our molecule can only retain this motion in one direc- tion at right angles to the exact one for which it is abolished ; but the movement up and…
Color Vision Defects
Internet Archive · Royal College of Surgeons of England · Public domain (published before 1931). Free to use for anything.
![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-351-242.webp)
