tween 1820 and 1920 had given what we call civilization a
chance to make many changes in the wild world of birds. During that time
lifeless hummingbirds had been made to perch upon the hats of
fashionable women; herring gulls had been robbed of their eggs and
killed for their feathers; shooting movements had been organized to kill
crows with shotgun or rifle, in order that more gunpowder might be sold;
the people of Alaska had been permitted to kill more than eight thousand
eagles in the last great breeding-place left to our National Emblem;
uncounted millions of Passenger Pigeons had been slaughtered, and these
wonderful birds done away with forever; and the methods by which egrets
had been murdered were too horrible to write about in books for children
to read.

But however shamefully civilization had treated, and had brought up
children to treat, these and many other of their fellow creatures of the
world, who had a right to the life that had been given them as surely
as it had been given to men, the years since 1820 had been happy ones
for the ancestors of Eve and Petro.

Eve and Petro, themselves, were happy as any two swallows need be that
spring of 1920, when they started forth to seek a cliff, just as their
ancestors had done for the hundred years or so since man began to notice
their habits, and no man knows for how many hundreds of years before
that.

Of course they found it as all cliff swallows must, for cliff-hunting is
a part of their springtime work. It was very high and very straight. Its
wall was of boards, and the gray shingled roof jutted out overhead just
as if inviting Eve and Petro to its shelter.

It was a good cliff, and mankind had been so busy building the same sort
all across the country for the past hundred years that there was no lack
of them anywhere, and swallows could now choose the ones that pleased
them best. Yes, civilization had been kind to them and had made more
cliffs than Nature had built for them; though perhaps it was Mother
Nature, herself, who taught the birds that these structures men called
barns and used inside for hay or cattle were, after all, only cliffs
outside, and that people were harmless creatures who would not hurt the
swallow kind.

However all that may be, it is quite certain that Eve and Petro
squeaked pleasantly for joy when they chose their building site,
undisturbed by the ladder that was soon put near, and unafraid of the
people who climbed up to watch