On this date in 1719, Mary (Marie) Hamilton, lady-in-waiting upon the tsaritsa Catherine I, was beheaded in St. Petersburg for infanticide. Lady Hamilton — her Scottish family had emigrated generations earlier — did not like to wait on her libido. She could tell you if Peter the Great deserved his nickname, and dish on any number of other courtiers, nobles, and hangers-on. This pleasing sport, of course, assumes with it the risks imposed by an equally impatient biology. Hamilton’s gallantries two or three times quickened her womb. Her decision to dispose of these unwanted descendants in the expedient way —...