TEE 
Viel od ONS 
Few truths can be more surprising when first we 
become aware of them than the indirectness of the 
communication of the mind with the external world 
through the senses. Our sensations, like our move- 
ments, are the results of action of most complex 
machinery working without our having knowledge 
of its structure, or even, it may be, of its existence. 
We have no consciousness of the myriad changes 
taking place within it before a momentary sensa- 
tion of sight, or sound, or touch can occur. 
Not only so, but it is impossible to give any 
reason why the peculiar actions of the various sen- 
sory mechanisms are followed by the particular 
sensation which they each induce. Thus, although 
science discovers to us the existence of vibrations of 
light and sound, we cannot say why the irritation of 
1 Tn greater part re-arranged from portions of two popular lectures. 
