[94]

Expression

I cannot find passage nervous Systems Bell p. 175. B. has described paper in Phil Transact 1821, 22, 23, 26. 29 on nervous system & much bearing on expression. —

It is report Essay in 2d Edit

[Expression, pp. 158-9: "Sir C. Bell explains12 this action in the following manner:—"During every violent act of expiration, whether in hearty laughter, weeping, coughing, or sneezing, the eyeball is firmly compressed by the fibres of the orbicularis; and this is a provision for supporting and defending the vascular system of the interior of the eye from a retrograde impulse communicated to the blood in the veins at that time. When we contract the chest and expel the air, there is a retardation of the blood in the veins of the neck and head; and in the more powerful acts of expulsion, the blood not only distends the vessels, but is even regurgitated into the minute branches. Were the eye not properly compressed at that time, and a resistance given to the shock, irreparable injury might be inflicted on the delicate textures of the interior of the eye." He further adds, "If we separate the eye-lids of a child to examine the eye, while it cries and struggles with passion, by taking off the natural support to the vascular system of the eye, and means of guarding it against the rush of blood then occurring, the conjunctiva becomes suddenly filled with blood, and the eyelids everted."
12 'The Anatomy of Expression,' 1844, p. 106. See also his paper in the 'Philosophical Transactions,' 1822, p. 284, ibid. 1823, pp. 166 and 289. Also 'The Nervous System of the Human Body,' 3rd edit. 1836, p. 175."]