Words ending in -ed are to be spelt so in all cases; and with a grave accent when the syllable is separately pronounced, thus—èd. (’d is not to be used.)
This applies to poetical quotations introduced into prose matter, and to new works. It must not apply to reprints of standard authors, nor to quotations in works which reproduce old spellings, &c.
Whenever a poetic quotation, whether in the same type as the text or not, is given a line (or more) to itself, it is not to be placed within quotation marks; but when the line of poetry runs on with the prose then quotation marks are to be used.
On spacing poetry, seep. 49.