Modern Chromatics

Abstract

IN NATURE, vol. xxi. p. 78, is a review of a book of mine, “Modern Chromatics,” by Silvanus P. Thompson, that contains one or two points that I ought perhaps not to allow to pass without notice. The statement is made by the reviewer that I claim as mine a certain experiment which was originally described in England by T. Rose. I find, however, on examination, that Mr. Rose read his paper on this subject before the British Association in 1861, while mine was published in September, 1860, in the American Journal of Science and Arts. In the same review it also stated or implied that I am in error in saying that in blue eyes there is no real blue colouring matter, but that the blue hue is due to the presence of a turbid (or opalescent) medium. Essentially the same statement with details will he found on p. 14 of Helmholtz's “Physiological Optics,” also on p. 610 of Dalton's “Human Physiology.” In his “Physiologic der Farben,” on p. 95, Brücke remarks:—“In the most beautiful blue eye there is no trace of any blue colouring matter.”