Good.
comperto is literally an impersonal ablative absolute: "with it not yet having been discovered..." The ablative absolute does have a causal sense though.
I just noticed, for
noscebant, "recognized" would be a better translation than "knew".
Even those whose friends or relatives were missing for another reason, they nevertheless feared for [them]
This still doesn't make complete grammatical sense. If you removed the relative clause, the sentence would read "Even those they nevertheless feared for [them]". The "they" is superfluous. I would get rid of the "for them" and just say "were nevertheless afraid".
A new passage, from Pliny. Some aspects of it are remarkably similar to the passage you just finished.
Iam cinis, adhuc tamen rarus. Respicio: densa caligo tergis imminebat, quae nos torrentis modo infusa 1
terrae sequebatur. 'Deflectamus' inquam 'dum videmus, 2
ne in via strati comitantium turba in tenebris obteramur.' Vix 3
consideramus, et nox — non qualis illunis aut nubila, sed qualis in locis clausis lumine exstincto*. 4
Audires ululatus feminarum, infantum quiritatus, clamores virorum; alii parentes alii liberos alii coniuges vocibus requirebant, vocibus noscitabant; hi suum casum, illi 5
suorum miserabantur; erant 6
qui metu 7
mortis mortem precarentur; multi ad deos manus tollere, plures nusquam iam deos ullos aeternamque illam et novissimam noctem mundo interpretabantur.
*The construction with
qualis is a bit tricky, and not easy to translate. It could be rephrased as
non talis nox, qualis illunis aut nubila nox, sed (talis nox), qualis... Think back to the
tantundem...quantum for an idea of how to translate the correlative pair
talis...qualis.
1. What case and why?
2. What type of clause?
3. Parse and give the first principal part.
4. Why subjunctive?
5. What is this doing? What must be implied with it?
6. What type of clause?
7. What is the name for the literary device where words derived from the same root are repeated with different endings?