Most aftershocks after a larger earthquake happen within a few days and then it becomes more random. So if they were terrified and they had quite a few felt aftershocks for a few days, after that it might be awhile until something was noteworthy, but they may have lost interest and stopped making notes. They didn't have an abundance of paper like we do now so that might make a difference.

One needs both time when they aren't supposed to be working and then paper to write when they have the time.

Petra