The mean ceramic date for the South Grove Midden is 1746. Historical archaeologists also rely on pipe stems to estimate when a site was occupied.
Dating sites using the principle that the bore diameter of a pipe stem regularly decreases over time has been around since the 1950s and has been subjected to statistical analyses and further refined.
In 1992, while searching for Sir Walter Ralegh's Lost Colony on Roanoke Island, North Carolina, excavators found fragments of aboriginal pipes smoked there by colonists in 15.
Louis Binford later devised a mathematical formula to refine Harrington's method (Deetz 19).
This dating technique only applies to pipe stems manufactured in England between approximately 15.
An early explanation for their ubiquity had it that in colonial-era taverns pipes passed from mouth to mouth, but that in the interests of hygiene the previously lip-gripped section was broken off and thrown away.
There is no documentary support for that notion, but it is known that used pipes were placed in iron cradles and heat cleansed in bake ovens before being issued to the next round of smokers.
But just as few of us give much thought to what later generations might deduce from our discarded bottle caps, no one in the eighteenth century considered how a twenty-first-century archaeologist might use his broken pipe as a clue to his life and time. The characteristics of tobacco pipes changed with the years, and if an archaeologist can date those changes, so can he date the objects with which they are are found.