Analysis of On the sight of swans in Kensington Gardens

Queen-bird, that sittest on thy shining nest
And thy young cygnets without sorrow hatchest,
And thou, thou other royal bird, that watchest
Lest the white mother wandering feet molest:
Shrined are your offspring in a crystal cradle,
Brighter than Helen's ere she yet had burst
Her shelly prison. They shall be born at first
Strong, active, graceful, perfect, swan-like, able
To tread the land or waters with security,
Unlike poor human births, conceived in sin,
In grief brought forth, both outwardly and in
Confessing weakness, error, and impurity.
Did heavenly creatures own succession's line,
The births of heaven like to yours would shine.