The notes of birds cease to affect us as they did.

February 5

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

I see another butcher-bird on the top of a young tree by the pond.

H. D. Thoreau, Journal, February 5, 1859

The loss of friends. See February 3, 1859 ("I perceive that we partially die ourselves through sympathy at the death of each of our friends or near relatives. Each such experience is an assault on our vital force. It becomes a source of wonder that they who have lost many friends still live.") Compare January 21, 1852 ("I never realized so distinctly as this moment that I am peacefully parting company with the best friend I ever had,"); February 8, 1857 ("And now another friendship is ended.")

The notes of birds cease to effect us. See  July 5, 1852 ("Some birds are poets and sing all summer. They are the true singers. Any man can write verses during the love season. ")

Another butcher-bird. See February 3, 1856 ("See near the Island a shrike glide by . . . with a remarkably even and steady sail or gliding motion"); March 1, 1855 ("Saw a butcher-bird, as usual on top of a tree, and distinguished from a jay by black wings and tail and streak side of head.") and note to December 24, 1858 ("See another shrike this afternoon, — the fourth this winter!") See also A Book of the Seasons, by Henry Thoreau, The Northern Shrike

the notes of birds cease 

to affect us as they did 

when we lose a friend