Saturday, August 16, 2008

Artifact of the Week

So here's the latest interesting artifact that has come out of the Port Tobacco collection.

Normally when I see a button, I just look to see what it's made out of: bone, shell, plastic, etc. I note the size and count them and add it to the catalog. Today, however, I came across one that was a bit different. It's brown and looks and feels like it could be bone but it also has lettering stamped on it. So, I put it under the magnifying glass to read what was written on it.

It reads: Goodyear N.R. Co. P=T

I know Goodyear makes tires, but buttons? Well the patent for the rubber hardening process was held by Charles Goodyear and thus had to have "P=T" and "Goodyear" which stands for patent held by Goodyear.

These "Goodyear" buttons were produced by the Novelty Rubber Company and the patent was in place from 1851-1872. These buttons were very commonplace in the 19th Century, so while not unique to Port Tobacco, it is an interesting find to this archaeologist and hopefully to you as well.

So what we have here is a middle of the 19th Century clothing button. I love coming across something other than ceramics that I can date! These buttons were very commonplace in the 19th Century, so while not unique to Port Tobacco, it is an interesting find to this archaeologist and hopefully to you as well.

- Peter

Friday, August 15, 2008

Middle Field Prehistoric Site

While we were collecting the plowed fields south of town, I noticed what appeared to be different lithic choices between the aboriginal peoples who occupied the Middle Field site and those who lived on sites in the other fields. Specifically, I noticed that many of the flakes and stone tools that we collected in the South Field were quartzites (metamorphosed quartz) of a pinkish or yellowish brown hue, while virtually all of the flakes recovered from the Middle Field (see map below) were white quartz.

Detail map of the Middle Field focusing on the prehistoric site.

Here's a breakdown of the flake types and materials for the Middle Field:

  1. Quartzite 2 Secondary
  2. Quartz 4 Shatter
  3. Quartz 8 Secondary
  4. Quartz 13 Primary
  5. Quartz 21 Decortication
  6. Chert 1 Core

Decortication flakes are those that retain portions of the cortex, or rind, of a pebble before it is broken. Primary flakes are generally large, rectangular, relatively flat flakes from which the stone tool maker (knapper) expected to make a tool. Secondary flakes are attempts to thin the blade of the tool. Typically they are trapezoidal and are curved. Tertiary flakes are small secondary flakes and result from sharpening the edge of a tool. Shatter are those flakes that cannot be classified because they were broken beyond recognition during knapping or long afterward by plowing and other activities. A core is a pebble whence the knapper removes primary flakes.

We didn't find any tertiary flakes (they are difficult to see, although we find them elsewhere). What we did find points to the collection of quartz pebbles from the stream and on-site manufacturing of stone tools, but not re-sharpening which probably occurred when the occupants of the Middle Field site moved elsewhere, bringing their tools with them.

The near absence of quartzite is interesting because it appears that both quartz and quartzite pebbles were locally available and probably occur in the streambed together. Why did the people living on the Middle Field site select quartz while the occupants of some of the other sites prefer quartzite, primarily of a pinkish or yellowish brown color? Was there some kind of significance attributed by some peoples to the quartzite or the colors it exhibited?

The samples, based on surface collections, are too small to say anything definitive, but future testing on the prehistoric sites south of town will take into account these differences and aim at determining if the occupants of these sites were different from one another. Colors have important spiritual significance in many American Indian cultures, present and past. Selection of material on the basis of color could suggest that one aboriginal group moved into an area already occupied or recently abandoned by another. Or it could indicate a shift in beliefs of a single group, with or without outside influence.

In future blogs I'll look at the distribution of lithic material types for the other sites.


Thursday, August 14, 2008

Serrated Triangular Projectile Point

Pete has been pulling some artifacts from the collection for display in our new traveling exhibit. From Unit 7, Stratum 3, the provenience from which we recovered a number of pieces of Potomac Creek pottery, comes this triangular point made from a quartzite decortication flake (a flake that retains some of the water-worn 'rind' of the pebble).

Serrated triangular arrowhead, about one inch in length.

This projectile point is interesting, not only because it was made from a decortication flake (a relatively unusual occurrence for any period) but because it is serrated. The maker of this arrowhead used a deer antler or some other soft material shaped like a punch or awl to remove small flakes from around the edge giving the object the sharpness of a serrated kitchen knife. Most triangular points dating to the Late Woodland are not serrated.

Archaeologist Stephen Potter, in his Commoners, Tribute, and Chiefs: The Development of Algonquian Culture in the Potomac Valley (University of Virginia Press, 1993), attributes these kinds of points to the Protohistoric and Historic periods (AD 1500-1650s). They are typically small ( not much more than a half inch in length) and, in Virginia's Northern Neck, are serrated isosceles triangles made from quartz.

Potter discusses movement of Indian tribes back and forth across the Potomac River and the development of the various tribes that formed the Conoy chiefdom, including the Piscataway and Portobacks. Continued excavation around Unit 7 may well contribute to Potter's larger story as it appears increasingly likely that the archaeology team has found a small Indian settlement dating to the first half of the 17th century; a community that was in direct contact with the Jesuit mission and the colonists whose increasing numbers led to the formation of Charles County 350 years ago.


Wednesday, August 13, 2008

A Note on White Salt Glaze Stoneware


Last October I posted about the White Salt Glaze Stoneware that was coming from the STP's in Port Tobacco. This summer during the ASM Field Session we started to unearth a different kind of White Salt Glaze Stoneware. This type didn't have the same "orange peel" effect that the earlier excavated wares did, and these new finds had a brown slip around the rim.

So, what's the difference and when did this occur?

By the mid 1720s, these types of "whitewares" were coming into Colonial America from England. They were an early attempt at creating a new style to compete with delftwares. They were coated with a white salt-glazed slip. During the firing process, the slip had a tendency to fall off the extremities (rims, spouts, tops of handles). To counteract this, these extremities were coated with a band of brown iron-oxide slip which we see on the shards we have excavated.

The introduction of block molds to create the basket and barley patterns that we have seen didn't come into production until the late 1730s and were manufactured well into the late 18th century. From about 1740 through the end of the 18th century both types were being made although the earlier form not as widely seen.

- Peter

Tuesday, August 12, 2008

Gottshalk's Sedimentation Model

I've been drafting some figures for the traveling exhibit, including one originally drawn and published by geographer L. C. Gottschalk in 1945. His paper, "Effects of Soil Erosion on Navigation in the Upper Chesapeake Bay" (Geographical Review 35[2]:219-238) describes the loss of navigable water around Colonial period towns in the Chesapeake region. He included Port Tobacco among his case studies and developed the model below to illustrate the problem.

I have added shading and colors to more clearly demonstrate the process. The upper figure shows the river at the end of the 18th century. The lower figures shows the source of sediments (red arrows), the sedimentation of the river and formation of wetlands (green), and the reduced extent of navigable water. This process destroyed the port over the course of a century. As early as 1775, a visitor noted that only small craft could navigate up to Port Tobacco. These might have been lighters, delivering goods and carrying off local agricultural products to ships lying at anchor in the Potomac River.

Sadly, sedimentation continues to this day, although not as severe as in the 19th century. Nonetheless, sediments and sewage continue to find their way into this beautiful river. Join us in studying the problem from an historical perspective and consider joining the Port Tobacco River Conservancy ( to help restore the Port Tobacco River. They are holding a fundraiser on Thursday, August 14, 7PM to 10PM, at the Port Tobacco Tiki Bar & Grill.


Monday, August 11, 2008

Buttons, Buttons, And More Buttons!

This is the first of several posts I will be doing on buttons. Now, why buttons? While we have found many plain buttons made of plastic, bone, ceramic and metal, very few come up which can be indentified. I will post on the buttons we can identify and date.

This first button was found in the 1st stratum of unit 22 (Centennial Hotel) by Dio and company. It is made out of a copper alloy (very thin and fragile). It depicts an American Eagle clutching 3 arrows in the left talon with a block lettered "I" upon an indented shield.

From the web research I have done, it appears to be a U.S. Infantry button dating to 1850-1865. While it is just one button, it should help us in our research for our Preserve America grant which is directed towards the Civil War era of Port Tobacco.

I haven't found information on who would have worn it (members of which Union units?) but I have sent out several inquiries on it and will post an update once I learn more.


The button indeed was used by the U.S. military from 1840-1865. Once the Civil War started, the button was only issued to Union troops. Unfortunately, without the back of the button, there is no further information on the manufacturing of the button. A thank you goes out to Harry Ridgeway, a collector of civil war era relics in Virginia, for his help in identifying our find.

- Peter

Sunday, August 10, 2008

Late Archaic House Sites?

Yesterday I wrote about the distribution of prehistoric Indian artifacts and what those distributions might tell us about the geological history of the Port Tobacco valley, especially about sedimentation. The PTAP team, of course, is interested in more than geology...we want to learn something about the various peoples who made the valley their home over the centuries. To that end, I've taken a closer look at the Indian artifacts that we mapped and recovered in what we call the Middle Field down near Warehouse Point.

The map below is an update of one that we've posted before. I drew 20 ft diameter circles around each flake, projectile point, potsherd, and fire-cracked rock that the team found. I then placed a 130 ft diameter circle (red) over each apparent cluster, placing the circles' centers over the approximate center point of each of four clusters. This simple form of graphical analysis produces results that suggest a degree of clustering consistent with what we might expect for the house sites of small groups, possibly extended families. There are statistical techniques that can be applied to the data...our rigorous data collection techniques allow that...and we will use them at some point; but I thought that the graphical technique would produce results readily understood by the largest number of readers.

Revised map of the Middle Field showing clusters of aboriginal artifacts.

The resulting model...a series of small settlements, probably seasonal...does not explain all of the data. There are other flakes and fire-cracked rocks that the team collected across the field and even one stemmed projectile point. These objects, however, appear to be scattered on the slopes descending from the northeast and the east, as depicted by the arrows. Those finds suggest eroded sites at the higher elevations that may extend into the forested areas that are not suitable for the surface collection and mapping strategy that we used in the plowed field.

We could take this analysis a step further by looking at the contents of each of the four clusters, or loci as archaeologists call such well-delineated scatters of material. Locus 4 has a number of fire-cracked rocks which are less common or absent in the other three loci. Did the inhabitants of Locus 4 roast acorns, hickory nuts, or various marsh plants on large stone hearths? Were they engaged in activities different from those of the occupants of the other three loci, or is this an artifact of sampling error? Perhaps test excavations will show that fire-cracked rock is equally common in all of the loci.

Locus 1 has a single pottery sherd associated with it. Does that sherd suggest that Locus 1 is later than the other loci, or is that sherd associated with another locus that extends to the banks of the creek? Might excavations at each of the loci produce pottery sherds sugesting that they all date to one of the Woodland periods?

The neat thing about these analyses is that they give us the opportunity to consider what might have happened in the past and how we might intelligently conduct additional fieldwork to collect data for even greater detailed analyses. Hopefully the team will return to these loci in the near future to further our understanding of early Indian life in the valley.