i remeber readin something like this but the other way aroundAncient Pharoahs had large stone walls that could be rolled from the kings chamber to the outside by means of hundreds of slaves rolling these thousands of tons slabs. In the cool of the desert night the wall would be rolled to the outside where it would cool rapidly in the night air. Just before sun up, the cooled slab of stone would be rolled back into the chamber where all day long it would "absorb" the heat of the room.
were theyd set these large rocks out during the day in the winter
and bring em in at night to heat the room