494 Scientific Proceedings, Royal Dublin Society. 



again, a nearly complete translation into judgments about space 

 relations has so transformed the many delicate muscular sensations 

 which accompany vision, that unless I direct special attention to 

 them I am not conscious of them as sensation at all. Instead of 

 being felt as sensations, they are another of the factors acting on a 

 part of the onto-brain which is wholly or partly outside my con- 

 sciousness, and inciting it to produce within my consciousness those 

 judgments about space relations that accompany vision. That we, 

 modern men, are endowed with such brains is part of the great in- 

 heritance that has come down to us from our ancestors ; and the 

 course of events in the universe is such, that we in our turn can 

 somewhat augment the store by judiciously exercising our faculties, 

 and so transmit a still greater possession to our posterity. 1 



But we need not pursue this inquiry farther : the fact is enough 

 for our present purpose. The tekmeria, the telegraphic messages 

 which reach me from the sense-compelling universe along the 

 several channels of telegraphic communication, present themselves 

 in my mind in the very much modified form of perceptions. Such I 

 experience to be the fact. 



It is very instructive to follow out the simile of a telegraph 

 somewhat further, with a view to our more clearly understanding 

 what has really occurred. Along a line of telegraphic communica- 



formed unconsciously so far as I am concerned) about space relations ; and in many, 

 perhaps in most, cases those tints are not appreciated by me as colour sensations at all, 

 unless I expressly scrutinise them under this special aspect. 



This remarkable transformation of sensations into something quite different from 

 sensation may be observed under circumstances which make it conspicuous, whenever 

 an extensive scene among mountains is viewed, especially in sunshine, first in the 

 ordinary erect posture, and then after inclining the head sideways, or, still better, after 

 turning it partly upside down. Under these latter circumstances a surprising amount 

 of colour, chiefly consisting of purples and greens, will seem to spring into existence, 

 which had been unseen as colour when the prospect was viewed from the erect 

 position ; and at the same time all the minor undulations of the surface, which were 

 conspicuous in the erect position, are now lost. In fact the wonderful instinct we 

 possess, by which we (with the co-operation of our synergos) effect the transformation 

 of sensations of colour into a judgment about form, is at fault when our eyes are 

 brought into a position markedly different from that in which they were when we 

 underwent the training which developed that instinct in us ; and accordingly the 

 sensation in its unaltered state is what then reaches us. 



1 Observe, in this connexion, the greater power of observation possessed by the 

 members of some families than of others, and especially by some individuals of those 

 families who have sedulously cultivated their powers of observation. 



