or with the advancing culture of the race, the habit of crying out
or screaming is restrained, and there is consequently no distension
of the blood-vessels of the eye, it may nevertheless well happen
that tears should still be secreted. We may see, as lately remarked,
the muscles round the eyes of a person who reads a pathetic story,
twitching or trembling in so slight a degree as hardly to be detected.
In this case there has been no screaming and no distension of the
blood-vessels, yet through habit certain nerve-cells send a small amount
of nerve-force to the cells commanding the muscles round the eyes;
and they likewise send some to the cells commanding the lacrymal glands,
for the eyes often become at the same time just moistened with tears.
If the twitching of the muscles round the eyes and the secretion
of tears had been completely prevented, nevertheless it is almost
certain that there would have been some tendency to transmit nerve-force
in these same directions; and as the lacrymal glands are remarkably
free from the control of the will, they would be eminently liable still
to act, thus betraying, though there were no other outward signs,
the pathetic thoughts which were passing through the person's mind.

As a further illustration of the view here advanced,
I may remark that if, during an early period of life,
when habits of all kinds are readily established, our infants,
when pleased, had been accustomed to utter loud peals of laughter
(during which the vessels of their eyes are distended)
as often and as continuously as they have yielded when
distressed to screaming-fits, then it is probable that in after
life tears would have been as copiously and as regularly
secreted under the one state of mind as under the other.
Gentle laughter, or a smile, or even a pleasing thought,
would have sufficed to cause a moderate secretion of tears.