Dear Dr. Staff: I'm always reading about those archaeologists unearthing all these ancient cities and finding lots of pots and vases and things. My question is: where did all the dirt come from?
Dear Hoghead: This is a particularly simple question. Those civilizations haven't been around for a long time, and nobody bothered to vacuum their rugs. However, all the vacuum cleaner bags that were sitting around, full of dirt and dust bunnies have decomposed, releasing their contents. This is how buried cities get that way.