Hump-backed ceiling joists?

This was from a 1890 house I inspected Friday. Any idea on what these “rounded” topped joists are for? There was about 4 or 5 of them installed above an upstairs bedroom. The rest of them were typical joists. Additionally; the hallway out of this room had a very evident slant that almost seemed like it was meant to be. There was no signs of out-of-the-ordinary-for-age-of-house settlement observations, but this floor was slanted, almost like it was built that way. I’ve been in a few older houses with normal slanted floors/settlement, but this one was definitely different.
Any helpful insight on either of these from you more experienced fellas more familiar with this era of construction practices would be greatly appreciated.

Thanks in advance…

Josh

rough sawn wood with only one side straightened is all i can think Josh…I had the opportunity to play in a saw mill a couple of times and it will look like that before You turn it around and make another pass…no real need for ceiling joists…just a wag…no ideas on the angled floor…

I think someone at the saw mill was thinking out of the box and trying to prevent deflection in the cieling joist by adding extra meat to the joist in the center. Seems somewhat counterintutitive but might be right on the money. Nobody is running the saw at the factory anymore. No room for innovation.

Could it have been for a low slope roof at a time in the past? Reclaimed material?

Needed extra height to keep the K&T wiring from igniting the ceiling.

I think Linda’s right.