singing is that expressed by Keats:

I was taught in Paradise
To ease my breast of melodies.

Precisely so. The overcharged breast can find no ease but in suckling
the baby-song. No enmity of outward circumstances, therefore, but his
own nature, was responsible for Shelley's doom.

A being with so much about it of child-like unreasonableness, and yet
withal so much of the beautiful attraction luminous in a child's sweet
unreasonableness, would seem fore-fated by its very essence to the
transience of the bubble and the rainbow, of all things filmy and fair.
Did some shadow of this destiny bear part in his sadness? Certain it is
that, by a curious chance, he himself in _Julian and Maddalo_ jestingly
foretold the manner of his end. "O ho! You talk as in years past," said
Maddalo (Byron) to Julian (Shelley); "If you can't swim, Beware of
Providence." Did no unearthly _dixisti_ sound in his ears as he wrote
it? But a brief while, and Shelley, who could not swim, was weltering on
the waters of Lerici. We know not how this may affect others, but over
us it is a coincidence which has long tyrannised with an absorbing
inveteracy of impression (strengthened rather than diminished by the
contrast between the levity of the utterance and its fatal
fulfilment)--thus to behold, heralding itself in warning mockery through
the very lips of its predestined victim, the Doom upon whose breath his
locks were lifting along the coasts of Campania. The death which he had
prophesied came upon him, and Spezzia enrolled another name among the
mournful Marcelli of our tongue; Venetian glasses which foamed and burst
before the poisoned wine of life had risen to their brims.