1893
Sept. 9
(No 2)
Concord, Mass.
  The forenoon was spent in planting hemlocks. In the
afternoon we took a long walk to Davis Swamp and
back by way of Bensen's and the open fields. Two
Brown Thrashers were seen and Chickadees and Blackpoll 
Warblers heard in several places.
  As we were reclining on the ground under a large pine
at the northern and of Davis Ridge, small objects began
falling in quick succession, rattling down through the
branches and striking the ground all about us. On
picking up one I found it to be the half of a
cup of a large green acorn. There must have been
a Squirrel concealed in the top of the pine but we
could see nothing of him.
  During the descent of the river and while at Ball's Hill
we had not seen a single Swift but at evening as we
were paddling past Holden's Hill five of these birds appeared
at a great height overhead and began descending and
cu[?][?]ing about after their usual fashion. Others followed them
and still others until by the end of the next four or five
minutes there were fully 75 darting back & forth
over the river & woods. They all came from the north, as
I could plainly see by watching the sky in that direction, &
evidently were migrating birds which merely made a brief
halt to secure their evening meal. For the remainder of the
way up the river Swifts were continually in sight either
flying low and feeding or keeping on directly south at a
height of 300 or 400 feet. All those which I saw after
sunset were flying high & towards the south. There can
be no doubt that what we witnessed was a veritable migration.
[margin]Heaving migration
of Swifts[/margin]