in Thoreau’s Journal:

When we have experienced many disappointments, such as the loss of friends, the notes of birds cease to affect us as they did.

February 5, 1841

Friday….There is something in the effect of a harmonious voice upon the disposition of its neighborhood analogous to the law of crystals; it centralizes itself and sounds like the published law of things. If the law of the universe were to be audibly promulgated, no mortal lawgiver would suspect it, for it would be a finer melody than his ears ever attended to. It would be sphere music.