Concord (Ball's Hill) April 21, 1904.
  Brilliantly clear with high, cold N. [north] wind.
Ground white with snow at sunrise. Some of it 
remained until nightfall.
  Spent day with Hansen & Pat transplanting
larches in Pine Park. At evening walked to Davis's Hill.
  At 7 a.m a Carolina Wren began singing near the 
cabin. As soon as I was dressed I rushed out & found
him perched in the very top of a tall white maple
just beyond the horse shed. Pat, who was with me,
says he heard him at the farm yesterday. He had a very
loud clear voice & sang 2 songs, Lots of birds about today.
Barn Swallow 2 [in a flock] & Swamp Sparrow (1) [in full song] arrived. Two Bubos
hooting on Pine Ridge this evening.