This answer to Any record of the Earth passing through the tail (not trail) of a comet? mentions
Earth passed through the tail of Halley's Comet in 1910. It caused a bit of a panic due to claims that cyanogen detected in the tail would cause harm: https://en.wikipedia.org/wiki/Halley%27s_Comet#1910
and links to the February 8, 1910 New York Times item Comet's poisonous tail; Yerkes Observatory Finds Cyanogen in Spectrum of Halley's Comet which includes the following sentence:
Only once, as far as known, has the earth passed directly through the tail of a comet, and at that time no unusual phenomena were noticed except that there were abundant showers of meteors.
Question: What comet's tail did Earth pass through before Halley's? This should be a recorded historic event, but it wouldn't necessarily have to have been recognized as such at the time. The goal here is to figure out most likely what event is being described in the quoted sentence.