Fascinating!
The Egyptians didn’t know either, so, like good tour guides to this very day, they just made up ****. One of the reasons Herodotus’ Historia is my fave is, he wrote down what he was told most of the time, often with his own reaction to the infor, and other times, he said, I’m not writing it down. For instance, he gave the various stories he was told about why the Nile floods out of season, including the correct one, then gave one of his own that’s completely ridiculous but culturally and temporally appropriate. :^)
The now-missing facing stones on the Great Pyramid had hieroglyphs carved on them, and Herodotus asked someone what it said:
[snip] On the pyramid it is declared in Egyptian writing how much was spent on radishes and onions and leeks for the workmen, and if I rightly remember that which the interpreter said in reading to me this inscription, a sum of one thousand six hundred talents of silver was spent... [/snip]