THE VOICES OF NATURE. 
149 
sphere round him. Then dream for a little while about 
sound, what it is, how marvellously it works outside in 
the world, and inside in your ear and brain ; and then, 
when you go back to work again, you will hardly 
deny that it is well worth while to listen sometimes to 
the voices of nature and ponder how it is that we hear 
them. 
