What is the connotative meaning of the word vacant in this line from the poem?

uselessly vacant, abandoned beside the easel

the word implies that the chair is not only empty, but unnecessary.

the word implies that the artist has chosen another chair.

the word implies that the chair is unattractive because it needs repair.

the word implies that the chair is confused about what has happened.

The connotative meaning of the word vacant in this line from the poem is that the word implies that the chair is not only empty, but unnecessary.

Explanation:

The definition of the chair being both empty and unnecessary can be inferred by the use of the expressions "abandoned", that means that it was occupied once and is no longer used, "uselessly vacant" expresses that there is no point in having an empty chair that nobody is going to use again. These expression are quite similar to the ones in the first definition.

it was surely an odd creature that one made up by reading the historians first and the poets afterwards a worm winged like an eagle; the spirit of life and elegance and charm,   in a kitchen chopping up suet. but these creatures, monst'r however entertaining to the imagination, hast no existence in fact. what one might doth to bringeth h'r to life wast to bethink poetically and prosaically at one and the same moment,   thus keeping in toucheth with fact—that the lady is mrs martin, ag'd thirty-six, did dress in blue, wearing a black coxcomb and brown shoeth; but not losing sight of fiction eith'r—that the lady is a vessel in which all s'rts of spirits and f'rces art coursing and flashing p'rpetually. the moment, howev'r, yond one tries this method with the elizabethan mistress, one brancheth of illumination fails; one is did hold up by the scarcity of facts.   one knoweth nothing detailed, nothing p'rfectly true and substantial about h'r.   hist'ry scarcely mentions h'r.   and i did turn to professeth'r trevelyan again to seeth what hist'ry meanteth to that gent.   i hath found by looking at his chapt'r headings yond t meanteth.