_Dilatation of the Pupils_.—Gratiolet repeatedly insists[1224] that the pupils are enormously dilated whenever terror is felt. I have no reason to doubt the accuracy of this statement, but have failed to obtain confirmatory evidence, excepting in the one instance before given of an insane woman suffering from great fear. When writers of fiction speak of the eyes being widely dilated, I presume that they refer to the eyelids. Munro’s statement, that with parrots the iris is affected by the passions, independently of the amount of light, seems to bear on this question; but Professor Donders informs me, that he has often seen movements in the pupils of these birds which he thinks may be related to their power of accommodation to distance, in nearly the same manner as our own pupils contract when our eyes converge for near vision. Gratiolet remarks that the dilated pupils appear as if they were gazing into profound darkness. No doubt the fears of man have often been excited in the dark; but hardly so often or so exclusively, as to account for a fixed and associated habit having thus arisen. It seems more probable, assuming that Gratiolet’s statement is correct, that the brain is directly affected by the powerful emotion of fear and reacts on the pupils; but Professor Donders informs me that this is an extremely complicated subject. I may add, as possibly throwing light on the subject, that Dr. Fyffe, of Netley Hospital, has observed in two patients that the pupils were distinctly dilated during the cold stage of an ague fit. Professor Donders has also often seen dilatation of the pupils in incipient faintness.[1225] _Horror_.—The state of mind expressed by this term implies terror, and is in some, cases almost synonymous with it. Many a man must have felt, before the blessed discovery of chloroform, great horror at the thought of an impending surgical operation. He who dreads, as well as hates a man, will feel, as Milton uses the word, a horror of him. We feel horror if we see any one, for instance a child, exposed to some instant and crushing danger. Almost every one would experience the same feeling in the highest degree in witnessing a man being tortured or going to be tortured. In these cases there is no danger to ourselves; but from the power of the imagination and of sympathy we put ourselves in the position of the sufferer, and feel something akin to fear. Horror and Agony. Fig. 21