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coloured hearers as well as coloured thinkers ; but we should 

 distinguish the person who has linked sensations, a synaesthete 

 from the person whose thoughts are coloured, whose mentation 

 is chromatic, who is, in fact, a psychochromaesthete. 



The literature of synesthesia is much more extensive than 

 any one would be inclined to think who had not made it a 

 special study. Nor is the condition described only in technical 

 publications ; there is an increasing tendency to recognise it in 

 current fiction. Thus in Dorian Grey we have : " her voice was 

 exquisite, but from the point of view of tone it was absolutely 

 false. It was wrong in colour." Musicians, it would appear, 

 are particularly liable to hear in colours : "The aria in A sharp 

 (Schubert) is of so sunny a warmth and of so delicate a green 

 that it seems to me when I hear it that I breathe the scent of 

 young fir-trees." The musical critic of the Birmingham Daily 

 Post thus once complained of a lady's singing : " Her voice 

 should have been luscious like purple grapes." Punch has, of 

 course, not failed to notice this tendency in musical criticism. 

 A writer in the Daily Telegraph had thus expressed himself : 

 " To a rather dark-coloured, deep, mezzo-soprano voice, the 

 singer joins a splendid temperament." Punch remarked : " We 

 ourselves prefer a plum-coloured voice with blue stripes, or else 

 something of a tartan timbre." 



Monsieur Peillaube (53), editor of the Revue Philosophique, has 

 reported on four persons who have well-marked coloured 

 hearing for organ notes, and he calls attention to the numerous 

 cases amongst musicians of definite associations between notes 

 and musical instruments on the one hand, and colours on the 

 other, as well as between whole pieces of music and colours. 

 Thus Gounod, endeavouring to express the difference between 

 the French and Italian languages, and giving his preference for 

 the former, used terms relating to colours: "Elle est moins riche 

 de coloris, soit, mais elle est plus variee et plus fins de tintes." 



Theoretically any two sensations may be linked, so that 

 coloured hearing is only one particular variety of synesthesia 

 (coupled sensations, secondary or dual sensations, Secondar- 

 empfindungen). No doubt the linking of colour with sound is 

 the commonest of these dual sensations, which, following 

 Bleuler (31), might be called sound-photisms. When a taste 

 produces light or colour we have a taste-photism ; similarly 

 there are odour-photisms, touch-photisms, temperature-photisms 



