Some babies born prematurely develop "retinopathy of prematurity", when the blood vessels in the eye grow abnormally resulting in damage to the retina and a loss of vision.
This child's disposition is abnormally cruel, merely for cruelty's sake, and whether he derives this from his smiling father, as I should suspect, or from his mother, it bodes evil for the poor girl who is in their power.
Is it possible that the Professor can have done it himself? He is so abnormally clever that if he went off his head he would carry out his intent with regard to some fixed idea in a wonderful way.
