construction history in the news…pyramids and grain
November 7, 2015 § 1 Comment
Not to get political, but this week one of the presidential candidates waded into architecturefarm territory by claiming that the Egyptian pyramids were built as grain storage by biblical figure Joseph to ensure his people would last through the mythic seven years of drought mentioned in Genesis. There may, in his words, have been aliens or divine inspiration behind both the form and the construction of the Pyramids. “The pyramids were made in a way that they had hermetically sealed compartments,” Carson said. “You would need that if you were trying to preserve grain for a long period of time.”
Well, yes. But if this theory was true you almost couldn’t find a dumber way to store grain. The largest of the pyramids contains a well-documented 2.5 million cubic meters of limestone and an equally well-documented 340 or so cubic meters of actual space. While we can argue about whether the dozens of artifacts found in the pyramids’ interior chambers represent burial rituals or carelessness on the part of granary employees who just happened to be carrying around religious artifacts, I think it’s pretty clear that 1/7400 is probably the worst net to gross ratio in the history of building. If the pyramids were in fact divinely-inspired granaries, the designer was having a particularly bad day.
Some quick math. There are about 640 calories in one cup of wheat berries. There are 4227 cups in one cubic meter. So the Great Pyramid could have held about 640 calories/cup x 4227 cups/cubic meter x 340 cubic meters/Great Pyramid, or about one billion calories of grain.
Sounds like a lot, until you do the math and realize that the average human consumes about a million calories a year. Even accounting for famine conditions and assuming that each Egyptian could get by on half of that, that means that each of the divinely-inspired granaries could have supported 2000 Egyptians for a year, or about 285 of them for the full seven year famine. Ok, ok, there were three “great” pyramids, but optimistically that means enough grain for roughly 900 Egyptians to get through a seven year famine.
Now, here’s the fun part. This month’s Scientific American has a great article on the actual construction of the Pyramids. In particular, it focuses on the work of archaeologists like Mark Lehner and Pierre Tallet, who have excavated the job site towns around the pyramids and discovered whole cities devoted to housing workers and laborers, and to managing the trade of metals, stones, and–yes–food to keep the construction sites going. Their findings are really fascinating. Among other things, there’s evidence that, far from being slave laborers, the workers who built the pyramids seem to have been ordinary citizens who may have been donating their labor out of religious devotion. And they’ve tracked trade routes as far away as the Sinai peninsula, suggesting that the organization and trading relationships that were formed to get the pyramids built served to raise the Egyptian economy far above its neighbors. The pyramids, according to Lehner, were more of a “sociological wonder” than a “technological wonder,” providing the economic and labor infrastructure that transformed the Egyptian state into a self-sustaining positive economic feedback loop that “not only created wealth for Egypt but also lifted the economies of its trading partners abroad.”
No surprise that this particular presidential candidate would scoff at that sort of Keynesian economic history. But more to the point, Lehner and others estimate that the size of the town housing the pyramids’ workforce was something like 6,000–in other words, seven times the population the pyramids could have fed if they were in fact granaries. And the towns had their own granaries to feed their residents that were far larger than the 340 cubic meters offered by the pyramids’ interiors.
In other words, the Pyramids as granaries would have been not only spatially inefficient, but not even as efficient as the warehouses in town used to feed the crews building them.
I don’t know about you, but this seems like a waste of taxpayer dollars to me.