+Stanza 50,+ 1. 3. One keen pyramid. The tomb (see last note) of Caius Cestius, a Tribune of the People.

11. 4, 5. The dust of him who planned This refuge for his memory. Shelley probably means that this sepulchral pyramid alone preserves to remembrance the name of Cestius:  which is true enough, as next to nothing is otherwise known about him.

1. 8. Have pitched in heaven’s smile their camp of death. The practice which Shelley follows in this line of making ‘heaven’ a dissyllable is very frequent with him.  So also with ‘even, higher,’ and other such words.

+Stanza 51,+ 11. 3, 4. If the seal is set Here on one fountain of a mourning mind. Shelley certainly alludes to himself in this line.  His beloved son William, who died in June 1819, in the fourth year of his age, was buried in this cemetery:  the precise spot is not now known.

11. 5-7. Too surely shalt thou find Thine own well full, if thou returnest home, Of tears and gall.  From the world’s bitter wind, &c.  The apposition between the word ‘well’ and the preceding word ‘fountain’ will be observed.  The person whom Shelley addresses would, on returning home from the cemetery, find more than, ample cause, of one sort or another, for distress and discomposure.  Hence follows the conclusion that he would do well to ‘seek shelter in the shadow of the tomb’:  he should prefer the condition of death to that of life.  And so we reach in stanza 51 the same result which, in stanza 47, was deduced from a different range of considerations.

+Stanza 52,+ 1. 1. The One remains, the many change and pass. See the notes on stanzas 42 and 43.  ‘The One’ is the same as ‘the One Spirit’ in stanza 43—­the Universal Mind.  The Universal Mind has already been spoken of (stanza 38) as ‘the Eternal.’  On the other hand, ‘the many’ are the individuated minds which we call ‘human beings’:  they ’change and pass’—­the body perishing, the mind which informed it being (in whatever sense) reabsorbed into ‘the Eternal.’

1. 2. Heaven’s light for ever shines, earth’s shadows fly. This is in strictness a physical descriptive image:  in application, it means the same as the preceding line.

11. 3-5. Life, like a dome of many-coloured glass, Stains the white radiance of eternity, Until Death tramples it to fragments. Perhaps a more daring metaphorical symbol than this has never been employed by any poet, nor one that has a deeper or a more spacious meaning.  Eternity is figured as white light—­light in its quintessence.  Life, mundane life, is as a dome of glass, which becomes many-coloured by its prismatic diffraction of the white light:  its various prisms reflect eternity at different angles.  Death ultimately tramples the glass dome into fragments; each individual life is shattered, and the whole integer of life, constituted of the many individual lives, is shattered.  If everything else written by Shelley were to perish, and only this consummate image to remain—­so vast in purport, so terse in form—­he would still rank as a poet of lofty imagination. Ex pede Herculem.