Friday, July 31, 2009


Hand and trowel screening of soil through a shaker screen does not recover all artifacts, particularly ones smaller than 1/4 inch. In special circumstances, in feature fill situations or other places where the recovery of small items is needed, water screening is an alternative process. This water screening device is used in the laboratory or in the field to clean and examine soil samples taken from archaeological features and sites. It was developed to retrieve small organic materials, such as seeds and bone fragments, as well as tiny flint chips, from archaeological deposits.

(Anne and Kelley waterscreening)

A mesh screen is put atop a larger screen with the soil put into the screen. It is then carefully hosed down with water and sorted. It is then set out to dry on a separate screen. After drying, the same material will then be 'floated' in a flotation tank to pull out any organic material. After that, it is cataloged and bagged like any other artifact.

*NB* This is very messy work!

Wednesday, July 29, 2009

Upcoming Lab Days

A reminder and update on our weekly lab days:
Scott will be running a lab at Port Tobacco this Saturday, 9 AM to 3 PM.
Tom Forhan will run the Crownsville lab days, Mondays 9 AM to 3 PM.
So far there has been enough participation and productivity to keep Anne and Kelley busy with cataloguing. We appreciate the help.

Another reminder of a different sort: the Charles County Archaeological Society will resume its monthly meetings in September after a two month summer hiatus. As always, everybody is welcome to join us on the second Tuesday of each month, 7:30 PM to 9 PM, generally in the Port Tobacco courthouse. Carol Cowherd will provide a schedule on this blog as soon as we have confirmed all of the dates and speakers. Attendees will hear about of chapter president Paula Martino's archaeological adventures in Israel, an update on the work this spring at Port Tobacco, recent discoveries on Early and Middle Archaic sites in the region, and a final report on the PTAP team's work this spring at a Union encampment outside of town. We will also announce our autumn excavation schedule in and around Port Tobacco. Stay tuned.


Tuesday, July 28, 2009

Interpretive Signs at Port Tobacco

The Interpretive Sign project, funded by Charles County and the Maryland Heritage Area Authority, moves apace. We should have several signs ready for design and fabrication shortly. Here is an example of what the introductory sign might look like (before a professional designer has had the opportunity to work some magic).

Mock up interpretive sign for Port Tobacco.

Sorry, it isn't readable at this point, but as soon as I've revised the content and a designer has worked on it, we will get it, and others like it, onto the Society for the Restoration of Port Tobacco's website. Visitors can comment on the sign's design and content. We will then arrange the signs as a virtual tour of the town site. Indeed, a number of signs probably will exist only on the web until funds have been secured to fabricate and install additional ones. At least three, initially, will be installed with available funds.


Monday, July 27, 2009

Making One More Point

At the risk of reiterating the same point, and wearing out readers' patience with more artless puns, I offer this last point.

Probable Calvert projectile point, Lot #669.

Made from a gray quartzite, this small stemmed point appears to be a Calvert projectile point, a type that may span several periods, from the Late Archaic into the Middle Woodland. It measure 0.9" (22 mm) long by 0.55" (14 mm) wide, and is 0.26" (7 mm) thick. It has an impact fracture; which is to say, the tip broke off, probably on impact, suggesting a projectile point rather than a hafted knife blade.

This piece came from the same context as the yellow jasper point that I wrote about yesterday. Unlike that piece, however, this point easily could have been made from locally available material.


Sunday, July 26, 2009

Exotic material

The photograph below does not do justice to the exquisite quality of yellow jasper from which this corner-notched projectile point was made, nor to the delicate percussion flaking that an Indian used to make it thousands of years ago.

Jasper--chemically similar to flint, chalcedony, and chert--is a sedimentary material comprised of silicates from the shells of microorganisms. In some materials, with magnification, one can see individual radiolaria, sponge spicules, and other fossils. The closest known sources for this material are in southeastern Pennsylvania. This particular piece came from the plowzone in Unit 48 at Port Tobacco.

Although made to tip a projectile, the point appears to have been adapted for use as a hafted knife, probably because wear, repair,and breaks had made it too asymmetrical and thick to meet the hafting and aerodynamic demands of a projectile. As a projectile, it was large. Even worn and resharpened, the point is 2. 4" (60 mm) long, 1.2" (31 mm) wide, and 0.3" (8 mm) thick.

Side-notched projectile points in this region typically are attributed to the Early and Middle Archaic periods, which is to say, in excess of 6,000 years old.