The Book of Thoth contained all the knowledge of the gods. It was nestled in the bottom of the Nile and locked in a series of boxes guarded by serpents. Many pharaohs tried to gain access to it during their reign, but it was never opened.
It's said that the knowledge in there was never meant to be possessed by mere mortals. Perhaps this helped the Egyptians make sense of the things they still couldn't quite understand. Somewhere - out there in the bottom of the Nile - lay all the answers.