[Foot-note 10: See the Appendix.] Adaptability made easier the diffusion of alliterative verse: but its revival was not due to a deliberate choice on practical grounds. It was a phase of a larger movement, which may be described as a weakening of foreign and learned influences, and a recovery of the native stock. And the metrical form is only the most obvious of the old-fashioned elements that reappeared. In spirit, too, the authors of the alliterative school have many points of kinship with the Old English poets. They are more moderate than enthusiastic. Left to themselves, their imaginations move most easily among sombre shapes and in sombre tones. They have not the intellectual brilliance and the wit of the French poets; and when they laugh—which is not often—the lightness of the thirteenth century is rarer than the rough note of the comic scenes in the Towneley plays. It is hard to say how much the associations and aptitudes of the verse react on its content: but _Sumer is icumen in_, which is the essence of thirteenth-century poetry, is barely conceivable in Old English, where even the cuckoo's note sounded melancholy; and it would come oddly from the poets of the middle fourteenth century, who have learned from the French _trouvères_ the convention of spring, with sunshine, flowers, and singing birds, but seem unable to put away completely the memory of winter and rough weather. In the last quarter of the century the tide of foreign influence runs strong again; and the work of Gower and Chaucer discloses radical changes in the conditions of literature which are the more important because they are permanent. The literary centre swings back to the capital—London now instead of Winchester—which henceforth provides the models for authors of any pretensions throughout England and across the Scottish border. In Chaucer we have for the first time a layman, writing in English for secular purposes, who from the range and quality of his work may fairly claim to be ranked among men of letters. The strictly clerical writers had been content to follow the Scriptures, the Fathers and commentators, the service books and legendaries; and Chaucer does not neglect their tradition.[11] The minstrels had exploited a popular taste for merry tales 'that sownen into synne'; and he borrowed so gladly from them that many have doubted his repentance.[12] But his models are men of letters:—the Latin poets headed by Ovid, who was Gower's favourite too; French writers, from the satirical Jean de Meung to makers of studied 'balades, roundels, virelayes' like Machaut and Deschamps; and the greater Italian group—Boccaccio, Petrarch, and Dante. Keeping such company, he was bound to reject the rusticity of the alliterative school, and the middle way followed by those who added a tag of rime at the end of a rimeless series (as in _Sir Gawayne_), or invented stanzas in which alliteration remains, but is subservient to rime (as in _The Pearl_ and the York plays).