Here’s a little translation that I commissioned of a page of book IV of John the Lydian “On the Months”. It’s relevant to our discussions of bruma. This translation is public domain – do whatever you like with it, commercial or educational.
The Romans customarily divided their citizenry into three [groups] and distinguished those who were suitable for arms, those [who were suitable] for farming, and those [who were suitable] for hunting; and the season of winter brings an end to these [pursuits]. For in it, neither do they arm themselves, nor do they practice farming, because of the season’s cold and the shortness of the days—and hence in the old days they named it bruma, meaning “short day.” And Brumalia means “winter festivals”; so at that time, until the Waxing of the Light, ceasing from work, the Romans would greet each other with words of good omen at night, saying in their ancestral tongue, “Vives annos“—that is, “Live for years.”
And the farming people would slaughter pigs for the worship of Cronus and Demeter—and hence even now the “Pig-Slaughter” is observed in December. And the vine-dressers would sacrifice goats in honor of Dionysus—for the goat is an enemy of the vine; and they would skin them, fill the skin-bags with air and jump on them. And the civic officials would also [offer as] the firstfruits of the collected harvest wine and olive oil, grain and honey and as many [products] of trees as endure and are preserved—they would make loaves without water and they would bring [all] these things to the priests of the [Great] Mother. And this sort of custom is still observed even now; and in November and December, until the “Waxing of the Light,” they bring [these] things to the priests. For the [custom] of greeting [people] by name at the Brumalia is rather recent; and, the truth [is], they call them “Cronian festivals”—and because of this the Church turns away from them. And they take place at night, because Cronus is in darkness, having been sent to Tartarus by Zeus—and they mysteriously signify the grain, from its being sown in the ground and thereafter not being seen. And this is quite true, as has been said: The attention to [these] things goes on at night, such that finally, in truth, the Brumalia are festivals of the subterranean daemones.
 Gk. Βρουμάλια δὲ οἱονεὶ χειμεριναὶ ἑορταί; alternatively, “…[function] as winter festivals,” but οἱονεί introduces the significance of a term just before, with bruma.
 Gk. τὰ Αὐξιφωτία, presumably referring to 25 Dec., as (e.g.) in the “Calendar of Antiochus” the date is marked: ἡλίου γενέθλιον· αὔξει φῶς. For the phrase, cf. also Cosmas of Jerusalem, Comm. in S. Greg. Naz. carm. [PG 38:464].
 Lit., “you will live for years.”
 I.e., Saturn and Ops, who were considered husband and wife, and whose festivals were associated at this time of year; some further considered them the equivalents of Heaven and Earth (Macrobius, Sat. 1.10).
 Cf. askoliasmos / Askolia, the name for such an “event” at the Rural Dionysia.
 I.e., the Magna Mater (Cybele) (?).
 Gk. τὸ…ἀληθέστερον; lit., “the truer [thing]” / “the quite true [thing].”
 I.e., Saturnian festivals (Saturnalia).
 Gk. ἀποτρέπεται; alternatively, “turns [people] away from them.”
 Gk. αἰνίττονται.