Margaret Nicholson, a delusional 36-year-old daughter of a Durham barber, approached George III as he stepped down from his carriage at St. James' Palace on 2 August. She carried a rolled document that appeared to be a petition, but when she was within reach she attempted to stab the king with an ivory-handled dessert knife. The knife broke on her second thrust, and the king escaped with only slight damage to his waistcoat ( DNB ).

“She was immediately taken,” Abigail Adams 2d reported in a letter to John Quincy Adams later that day. “His Majesty tis said desired she might not be Hurt as he was not injurd. This request prevented her being torn in peices by the Guards and she was taken into Custody and is said to be Insane. . . . She has since been examined, and is to be tried in a few days. It is Supposd She will be Confind in a priests Mad House for Life.” Nicholson was examined by the Privy Council, declared insane, and committed to Bethlehem (Bedlam) Hospital, where she resided until her death in 1828. William Stephens Smith reported to the Adamses on 8 August that “Margaret Nicholson is still in confinement and furnishes Paragraphs and Prints,” one of which, published by Carington Bowles, is reproduced here ( DNB ; Abigail Adams Smith to John Quincy Adams, 27 July 1786; William Stephens Smith to John and Abigail Adams, 8 Aug. 1786, both below).

While the king was unruffled by the attack, Queen Charlotte and the couple's children were overcome. “It was an evening of grief and horror to his family,” a contemporary observer wrote. “Nothing was listened to, scarce a word was spoken; the Princesses wept continually; the Queen, still more deeply struck, could only, from time to time, hold out her hand to the King, and say, 'I have you yet!'” The public was equally moved and crowded the royal family's carriage shouting huzzas when the king and queen toured Kew Gardens on 8 August. “I shall always love little Kew for this,” Queen Charlotte reportedly told her husband (Christopher Hibbert, George III: A Personal History, N.Y., 1998, p. 227; John Brooke, King George III, N.Y., 1972, p. 315).