The first time I saw the bathing folios (the ones with lots of nymphs in the pools), they struck me as instructional. In other words, it didn't look to me like a record of people bathing (historical), but rather a step-by-step instruction on how to bathe (perhaps for therapeutic reasons?).
Not the pool with the rainbows, however. That one seems different, more like a narrative.
Not the pool with the rainbows, however. That one seems different, more like a narrative.