In the fifth edition of Dr. Thomas Bull's The Maternal Management of Children (1854) the following remarkable instance of the putative effect of strong mental excitement on breast milk is given.
A carpenter fell into a quarrel with a soldier billeted in his house, and was set upon by the latter with his drawn sword. The wife of the carpenter at first trembled from fear and terror, and then suddenly threw herself furiously between the combatants, wrested the sword from the soldier's hand, broke it in pieces, and threw it away. During the tumult, some neighbours came in and separated the men. Whilst in this state of strong excitement the mother took up her child from the cradle, where it lay playing, and in the most perfect health, never having had a moment's illness; she gave it the breast, and in so doing sealed its fate. In a few minutes the infant left off sucking, became restless, panted, and sank dead upon its mother's bosom. The physician who was called in found the child lying in the cradle as if asleep, and with its features undisturbed; but all his resources were fruitless. It was irrecoverably gone. The milk in this striking case must have undergone a change, which gave it a powerful sedative action upon the susceptible nervous system of the infant.