@dalehileman,
ORIGINAL: On turning a corner out of a narrow coppice-bordered lane into a wider road that sloped steadily upward in a long stretch of hill Elaine saw, coming toward her at no great distance, a string of yellow-painted vans, drawn for the most part by skewbald or speckled horses. A certain rakish air about these oncoming road-craft proclaimed them as belonging to a travelling wild-beast show, decked out in the rich primitive colouring that one’s taste in childhood would have insisted on before it had been schooled in the artistic value of dulness.
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Dale: Per your implication trouble is one of number
jtt:I don't understand you here, Dale.
Based on
….road-craft proclaimed them (plural) as belonging to a travelling wild-beast show….. (singular)…..not completely justified.
Thus the comma seems to imply singular
"…the wild-beast show, decked out as it was in…"
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I don't recall suggesting/implying that the trouble was/is one of number, Dale. And I don't now see any trouble as regards number.
I may be mistaken but I think it is far beyond the capacity of a simple comma to state, let alone imply grammatical number.
I'd say that the indefinite article 'a' is what describes singular.