While he was yet residing in Marlow, the Princess Charlotte, daughter of the Prince of Wales (afterwards George IV.,) died; and, since her character had been in strong contrast with her father’s and with royal persons’ in general, her early death seems to have caused, not only ceremonial mourning, but also genuine regret amongst all in the community having any knowledge of her exceptional amiability. The poet seized the opportunity of so public an event, and published _An Address to the People on the Death of the Princess Charlotte. By the Hermit of Marlow_, in which he inscribed the motto--“We pity the plumage, but forget the dying bird.” In this pamphlet, while paying due tribute of regret for the death of an amiable girl, and fully appreciating the sorrow caused by death as well among the destitute and obscure (with whom, indeed, the too usual absence of the care and sympathy of friends intensifies the sorrow) as among the rich and powerful, he invited, in studiously moderate language, attention to the many just reasons for national mourning in the interests of the poor no less than of princes; and, in particular, invited the nation to express its indignant grief for the fate of the Lancashire mechanics who, missing the happier fate of their brethren slaughtered at Peterloo, were subjected to an ignominious death by a government which had, by its neglect, encouraged the growth of a just discontent. In 1818 Shelley left England never to return. At this time was composed the principal part of his masterpiece--_Prometheus Unbound_, the most finished and carefully executed of all his poems. While in Rome (1819) he published _The Cenci_, which had been suggested to him by the famous picture of Guido, until lately supposed to be that of Beatrice Cenci, and by the traditions, current even in the poet’s time, of the cruel fate of his heroine. Shakspere’s four great dramas excepted, _The Cenci_ must take rank as the finest tragic drama since the days of the Greek masters. It is worked up to a degree of pathos unsurpassed by anything of the kind in literature. “The Fifth Act,” remarks Mrs. Shelley, his editor and commentator, “is a masterpiece. Every character has a voice that echoes truth in its tones.” _The Cenci_ was followed in quick succession by the _Witch of Atlas_, _Adonais_ (an elegy on the death of Keats), the most exquisite “In Memoriam”--not excepting Milton’s or Tennyson’s--ever written; and _Hellas_, which was inspired by his strong sympathy with the Greeks, who were then engaged in the war of independence.