Slant Rhyme
https://www.oxfordreference.com/view/10.1093/oi/authority.20110803095916473
This article provides a helpful technical definition of slant rhyme and gives some historical background for its usage and development in literature.
The Question and Answer section for Hope is the Thing with Feathers is a great resource to ask questions, find answers, and discuss the novel.
Best results for your answer
What does the writer want the reader to see, hear, taste, feel and smell?
I think the natural elements, oftemn extreme, are evocotave.
sweetest in the gale is heard;
And sore must be the storm
I've heard it in the chillest land,
And on the strangest...
Chillest in Dickinson's day actually meant cold. It soulds like she means laid back as in "chill" in Hawaii but it means cold like in the Yukon so she is saying, I've heard in the coldest land.