vessels, thus induced, might act by reflection on the lacrymal
glands the effects due to the spasmodic pressure of the eyelids on the
surface of the eye being thus increased.
In considering how far this view is probable, we should bear in mind
that the eyes of infants have been acted on in this double manner
during numberless generations, whenever they have screamed; and on the
principle of nerve-force readily passing along accustomed channels,
even a moderate compression of the eyeballs and a moderate distension
of the ocular vessels would ultimately come, through habit, to act on
the glands. We have an analogous case in the orbicular muscles being
almost always contracted in some slight degree, even during a gentle
crying-fit, when there can be no distension of the vessels and no
uncomfortable sensation excited within the eyes.
Moreover, when complex actions or movements have long been performed in
strict association together, and these are from any cause at first
voluntarily and afterwards habitually checked, then if the proper
exciting conditions occur, any part of the action or movement which is
least under the control of the will, will often still be involuntarily
performed. The secretion by a gland is remarkably free from the
influence of the will; therefore, when with the advancing age of the
individual, 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
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