After him [Shahlûk] reigned his son Surid. He was an excellently wise man; and he was the first who levied taxes in Egypt, and the first who ordered an expenditure from his treasuries for the sick and the palsied, and the first who instituted the observation (?) of daybreak. He made wonderful things; among which was a mirror of mixed metal, in which he would observe the countries, and know in it the occurrences that happened, and what was abundant in them, and what was scarce. He placed this mirror in the midst of the city of Amsûs [the antediluvian capital of Egypt], and it was of copper. He made also in Amsûs the image of a sitting female mining a child in her lap. * * * That image remained until the Flood destroyed it: but in the books of the Copts [it is said] that it was found after the Flood, and that the greater part of the people worshipped it. * * * This Surid was he who built the two greatest Pyramids in Egypt, which are ascribed [also] to Sheddâd, the son of Ad; but the Copts deny that the Adites entered their country by reason of the power of their magic. When Surid died he was buried in the Pyramid, and with him his treasures. It is said that he was 300 years before the Flood, and that he reigned 190 years. After him reigned his son Harjîb; he was excellently wise, like his father, in the knowledge of magic and talismans. He made wonderful things, and extracted many metals, and promulgated the science of alchemy. He built the Pyramids of Dahshûr, conveyed to them great wealth, and choice jewels, and spices, and perfumes, and placed on them magicians to guard them. When he died he was buried in the Pyramid, and with him all his wealth and rarities.
Source: “Bunsen’s Egypt and the Chronology of the Bible,” The Quarterly Review 105 (1859), 390-391.
Well, there you have it. Case closed! But seriously, I can't see anything in this besides a medieval legend trying to wed the pyramids to the Islamic notion (shared by the Jews and Christians) of the antediluvian world. Actually, if I were an ancient astronaut theorist I'd be more interested in the idea of a "mirror of mixed metal" that lets someone see things happening in other regions--a prehistoric iPad!