[16] According to a letter written by the poet Campbell to Mrs. Fletcher, in 1833, and published in her Autobiography, it was thought Shakspeare went in person to see this magic valley. 'It is no later than yesterday,' wrote Campbell, 'that I discovered a probability--almost near a certainty--that Shakspeare visited friends in the very town (Brecon in Wales) where Mrs. Siddons was born, and that he there found in a neighbouring glen, called "The Valley of Fairy Puck," the principal machinery of his "Midsummer Night's Dream."'