[18] Page 121, 306, 326, 387. [19] Page 306. [20] Page 104, 369. [21] Page 236, 260, 328. [22] "De' semplici colori il primo è il bianco: beuchè i filosofi non accettano nè il bianco nè il nero nel numero de' colori."--p. 125, 141. Elsewhere, however, he sometimes adopts the received opinion. [23] Leon Battista Alberti, in like manner observes:--"Affermano (i filosofi) che le spezie de' colori sono sette, cioè, che il bianco ed il nero sono i duoi estremi, infra i quali ve n'è uno nel mezzo (rosso) e che infra ciascuno di questi duoi estremi e quel del mezzo, da ogni parte ve ne sono due altri." An absurd statement of Lomazzo, p. 190, is copied verbatim from Lodovico Dolce (Somma della Filos. d'Arist.); but elsewhere, p. 306, Lomazzo agrees with Alberti. Aristotle seems to have misled the two first, for after saying there are seven colours, he appears only to mention six: he says--"There are seven colours, if brown is to be considered equivalent to black, which seems reasonable. Yellow, again, may be said to be a modification of white. Between these we find red, purple, green, and blue."--_De Sensu et Sensili_. Perhaps it is in accordance with this passage that Leonardo da Vinci reckons eight colours.--_Trattato_, p. 126. [24] Page 122, 142, 237. [25] On the authority of this explanation the word μιλάν has sometimes been translated in the foregoing extracts _obscurity, darkness_. Raffaello Borghini, in his attempt to describe the doctrine of Aristotle with a view to painting, observes--"There are two principles which concur in the production of colour, namely, light and transparence." But he soon loses this clue to the best part of the ancient theory, and when he has to speak of the derivation of colours from white and black, he evidently understands it in a mere atomic sense, and adds--"I shall not at present pursue the opinion of Aristotle, who assumes black and white as principal colours, and considers all the rest as intermediate between them."--_Il Riposo_, 1. ii. Accordingly, like Lodovico Dolce, he proceeds to a subject where he was more at home, namely, the symbolical meaning of colours. [26] This word is only strictly applied to unctuous substances, and may confirm the views of those writers who have conjectured that asphaltum was a chief ingredient in the _atramentum_ of the ancients. [27] "Elements of Physiology," by J. Müller, M.D., translated from the German by William Baly, M.D. London, 1839. NOTE N.--Par. 246. "The appearance of white in the centre, according to the Newtonian theory, arises from each line of rays forming its own spectrum. These spectra, superposing each other on all the middle part, leave uncorrected (unneutralised) colours only at the two edges."--S. F.[1]