--good blood, bad blood, proud blood, humble blood, honest blood,
thieving blood, heroic blood, cowardly blood. The tendency may skip a
generation or two, but it is sure to come out, as in a little child
you sometimes see a similarity to a great-grandfather whose picture
hangs on the wall. That the physical and mental and moral qualities
are inheritable is patent to any one who keeps his eyes open. The
similarity is so striking sometimes as to be amusing. Great families,
regal or literary, are apt to have the characteristics all down
through the generations, and what is more perceptible in such families
may be seen on a smaller scale in all families. A thousand years have
no power to obliterate the difference.