Lancaster, Mass.
1903.
June 19
  Cloudy with S.E. wind & occasional light showers.
  During a visit to Lancaster on May 24th last
I noticed a large number of Bank Swallows flying about
over the river just above the bridge near Miss Holman's
and entering - or issuing from - their nesting holes in a
neighboring bank. It was evidently a newly-established
colony for no birds had bred on this particular stretch
of river in 1901 or 1902. Visiting the place this afternoon
I counted 108 holes but greatly to my surprise there
was not, at first, a single bird in sight. At length, however,
a single pair appeared and during the next half hour
I saw one or both of these birds enter a hole (always the
same hole) several times with food for the young.
  Feeling sure that something must be wrong I finally descended
to the river and examined the bank attentively. For a distance
of about 8 ft. back from the water's edge the surface of the
ground was sandy or gravelly and sloped only very gently
upward. Above this for a distance of perhaps 6 ft. (measured
along the surface) the slope was at an average of about 45 degrees
and the sail, like that of the vertical bank still higher up,
five, smooth, hard-packed sand. The vertical portion
averaged about 2 ft. in height and was slightly overhung
in places by the loamy turf of the pasture land above
and behind. All the Swallows holes were, of course, in
the vertical face of the bank, some of them just under
the (?) and nearly all nearer the top than the bottom
of the vertical part. A glance satisfied me that the
village boys had not been tampering with them for none
of them showed any traces of enlargement. What, then,
could have driven the birds away from so apparently safe