Shelley showed his translation to Medwin in 1820, but there seems to be no record of the date of composition.
[77] An air with this title was published about 1800 in London by Robert Birchall.

See _Catalogue of Printed Music Published between 1487 and 1800 and now in the British Museum_, by W.Barclay Squire, 1912.

Neither author nor composer is listed in the _Catalogue_.
[78] This paragraph is materially changed from _F of F--B_.

Clouds and darkness are substituted for starlight, silence for the sound of the wind.

The weather here matches Mathilda's mood.