Within thy Grave — Nightmare

This poem is written for those who dislike Dickinson's death poems, or consider her poetry a nightmare. Her good intent hides in her darkness.

Within thy Grave!
Oh no, but on some other flight－
Thou only camest to mankind
To rend it with Good night－

(F.1582/J.1552)

[1] thy:: nightmare's. Grave:: the place where nightmare dwelt.
[2] flight:: thoughts that fly in a dream.
[3] only, mankind:: something that only mankind has or knows.
[4] Good night:: it appears after we said good night. Night hints at nightmare. rend, Good night:: a hint that nightmare ruins a fair night.

But when, in ebon mirror, Nightmare fell,
To tyrant or impostor bids them rise,
Black-winged demon-forms — whom, from the hell,
His reign and dwelling beneath nether skies,
He loosens to their dark and blasting ministries.
─ The Poetical Works of Percey Bysshe Shelley (1865)

The question is then the origin of the poem. Why nightmare? Dickinson's death poems can be a nightmare for some. This poem shows that the truth is hidden. The key is in line two, "but on some other flight" — some other good dark intent has escaped.

[1] Grave:: solemnity, soberness; Dickinson's solemn poetry.
[2] other flight:: other escaped meanings of her poems.
[3] mankind:: human beings with inborn nature.
[4] Good:: attractive, comely, fair. night:: darkness, gravity of her poems.