Friday, April 3, 2009

Pushing the Limits of Sampling

Apropos April's comment about yesterday's blog, all sampling techniques have their strengths and weaknesses. Shovel testing is an effective tool in many, but not all cases. (It isn't very effective, for example, in identifying battle sites, cemeteries, and mills.) Our close-interval (25 ft) sampling in Port Tobacco, complemented by controlled surface collecting in the plowed fields, has led to the identification of many historic and prehistoric sites.

One might wonder, however, what we would have found if we employed other methods as well; e.g., metal detecting in the plowed fields might have identified outbuildings based on clusters of nails which are easily missed in surface collecting. Geophysical techniques such as magnetometry and ground penetrating radar in the town core might have revealed many distinct building footprints. Infrared photography undertaken in 1970 produced potentially useful results, identifying building sites. Unfortunately, the original photographic slides have been lost, so the original data are no longer available.

There are limitations to what we can do with the resources at hand, but the PTAP team will always use whatever we have to the extent possible. We'll also experiment with new methods and use old methods in new ways.

Jim

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