At the Bird-Houston Site we spent much of the week working on an archaeological mystery. The largest feature on the site is this pit, which measured about 10 by 11 feet. One quarter of the feature was dug last year during the testing phase. This showed that the pit was roughly cone-shaped, and that it was intentionally filled in sometime around 1800. But what was it? Nobody had a convincing theory, except maybe that someone started digging a well or cellar and then gave up without finishing. This year we dug more of the feature. After shoveling out several hundred pounds of silt we discovered that what we thought was the bottom of the pit was not. It was a layer of soil that looked like the natural subsoil, but someone had dug it up and dumped it into the pit. Below this layer was more soil like the layers above. The pit had a false bottom, and the archaeologists had been fooled by it. So the crew kept digging, and eventually they found the edge of the feature started diving straight down. The lower part of the feature is a shaft, almost certainly a well. Sometimes archaeologists can tell what a feature is just by glancing at it, but sometime the only way to know is to dig all the way to the bottom.