Note 177 — Chapter VII · BACHELOR-SCHOLAR AND FELLOW OF TRINITY—1854 to 1856—Æt. 22-24.

The “colour-box,” though perfected only in 1862, was in full operation in the study at Glenlair several years before this—I think as early as 1850. And even then he had begun spinning coloured discs, proportionately arranged, so as to ascertain the true “mixture of colours.” He was fond of insisting, to his female cousins, aunts, etc., on the truth that blue and yellow do not make green. I remember his explaining to me the difference between pigments and colours, and showing me, through the “colour-box,” that the central band in the spectrum was different from any of the hitherto so-called “primary colours.” His theory on this subject was gradually formed through an immense number of ingeniously arranged observations.

His interest in Faraday’s investigations must have dated from a very early time, certainly before 1849. And now he sought to give to these speculations, at which his imaginative mind had long been working, precise mathematical expression. I wish I could recall the date (1857?) of a drive down the Vale of Orr, during which he described to me for the first time, with extraordinary volubility, the swift, invisible motions by which magnetic and galvanic phenomena were to be accounted for. It was like listening to a fairy-tale. For the substance of it see his papers in the Philosophical Magazine for 1861-2.