What is significant about the word order in "The poetry of earth is ceasing never," in John Keats' poem "On The Grasshopper and The Cricket"?

This is a very interesting question the answer to which
involves a discussion of negation in English and present participles. First let's look
at negation in English. The negator
never is an inherently negative adverb
that may function as a constituent negator. This means it is always negative and may
negate a single part of a sentence in addition to its function of negating a whole
sentence: e.g., (constituent negation) I think he never sings; (sentence negation) Never
carry antique chairs by the rungs.
Never may precede the verb: She never
cooks fish. Never may follow the verb:
She is never coming.

Now to
Keats. Keats uses poetic variation in positioning the negating adverb
never to optimize his meter and in
order to emphasize his dramatic point relating to the poetry of earth. Keats positions
never behind the present participle
ceasing rather than behind the to be linking
verb is, as in "She is never coming."
The present -ing participle
ceasing comprises part of the compound
present progressive verb (also called continuous progressive verb)
is ceasing (i.e., simple present
to be + -ing
participle).

According to current Standard
English (both U.S.A. and U.K.), the negator
never would be placed following
is and would be the constituent
negator in the compound verb. In other words, negative
never in current standardization would
follow the linking verb and precede the present participle, producing
is never
ceasing.

It is interesting to
note however that standardization for placement of this negating adverb
never did not occur until sometime
during or after the nineteenth century. In Keats' time, it was still commonly acceptable
in varius English dialects to locate
never in phrase-final position in the
same pattern that you might use for a non-negating adverb, as in "He is cleaning
carefully" or "She is sleeping soundly." In
summary, the significant thing about the wording in this quotation is that the negating
adverb never is in a dialectical
phrase-final position instead of in the standardized position following the
to be verb. The reason for the
variation in placement is because it heightens poetic effect and
meaning.