Telling Time by the Sun

By using an Egyptian gnomon, we charted the changes in the sun’s position around a fixed point throughout the day. We later created a shadow clock–a device that appears on the walls of an Egyptian tomb. It has a merkhet, or a vertical bar, for casting a shadow onto a base. It is ruled with 4 tick marks, presumably to correspond to hours. By aligning the clock with the east until it is perfectly level via a plumb-bob the shadow cast should correspond with a tick mark. In my experiment it did not, but that was because i interpreted the length of a palm to be my actual palm, which caused my merkhet to be very short.

Published in: on February 15, 2011 at 3:45 pm  Leave a Comment  

Projectile Creation

Our lab looked at the evolution of projectile-throwers in prehistory starting with the sling and the Baton de Commandment. Although I didnt get the opportunity to participate in the execution of the experiment, I assisted in the creation of the darts. We created 20 darts,  charted their weight in Kg, their caliper sizes on the top and bottom, and their overall length. From what I understand the batons worked well enough, but a lack of technique on the part of the throwers kept the projectiles from reaching their full potential.

Published in: on February 15, 2011 at 3:41 pm  Leave a Comment  

Lithic Use-wear Analysis

As the graduate student in the Experimental Archaeology class, I lectured and ran two labs on the analysis of lithics through patterns of use, or micro-wear analysis. In the lecture, I spoke of the current timeline we have of the development of stone or lithic technology. Starting with the Olduwan Industrial Complex some 2.7 to 2.9 million years ago, we see the use of simple stone choppers, hammers, and anvils that were used by Australopithecus through Homo Heidelbergensis in central Africa. Moving through the Acheluian, I talked of the Levalois technique and the Solutrean assemblages.

Micro-wear analysis looks at the patterns of wear on the edge of lithic artifacts and attempts to explain them through experimental archaeological analogy. We know that through use, the “business” end of a blade or artifact will become worn over time. By looking at the evidence on the artifact–in our case the striations created by motion–we can compare that to data from experiments that have been carried out. Longitudinal motion creates striations parallel to the edge and they are evident from cutting or sawing. Transverse motion creates stiations perpendicular to the edge and are from scrapping. Rotary motion creates round striations and wear and is created from drilling.

I set up experiments where students would scrape, saw, cut, and burrow into different materials, then we later looked under the microscope at the edges to determine if we could see striations that correlated to the motions that should have created them. We butchered the back legs of a deer and discovered that flint blades are very, very sharp and only a small one is capable of quickly butchering an entire leg rather quickly. We discovered that the harder the material, the harder we had to press on the blade to do work, and subsequently the associated striations were deeper and more defined.

We also tried to see if grass cutting left a sheen or polish on the blade by cutting green grass using over 1,000 stokes. While the chlorophyll stained the flint, no discernible polish was recognizable. I found that the students responded positively to this experiment because of their willingness to participate, the retention of information from the previous lecture, and the understanding of the scientific reasoning behind the experiments.

Published in: on February 15, 2011 at 3:30 pm  Leave a Comment  

Making Pottery & Understanding Ceramics

The process by which our ancestors made pottery is wonderful and extraordinary. To take minerals from the ground and create objects which have lasted a millenia is a testament to their ingenuity.

We started our understanding of pottery by heading over to NSU’s Art Department to watch pottery expert Matt DeFord and get out hands dirty.

We created pots by two methods that day–slab and wheel-thrown. Slab pottery is the use of a large wedge of clay that is shaped in place into a vessel of some sort. Wheel-thrown is the classic view of pottery creation–a wedge of clay in the middle of a rotating disc that is pulled into fantastic shapes and designs (or in the case of my piece…not so much). We also learned about Maria Martinez, a potter of San Ildsafanso, who uses a coil design to make pinch-pots

In our next pottery experience, we explored the methods by which clays are selected, processed, refined, and prepared for vessel creation. Dr. Gregory supplied us with some local Natchitoches clay and we processed the large, hard pieces with some hammer stones and anvils we had in the lab. The fine clay dust was consolidated into a large bucket. We sifted everything to remove large ferrous inclusions and other irregularities. Next, Dr. Hailey added water to the clay mixture and let it soak for a few days. We later hung the huge wedge of clay from a cedar tree outside of Kyser Hall to dry for the afternoon before working it.

Once our clay was sufficiently dry, we went to Dr. Gregory’s lab to look at some examples of decoration in pottery. Our goals in this lab was to replicate the designs that those of in the past here in the present. By using some of Dr. Gregory’s clay and mixing it with the clay that we had created earlier, we made an agate of the two with the coloring and characteristics of each mixed together. I created two pots–a large seed-like pot and a small bell-shaped pot. In my larger pot I used a process called punch-drag to try and replicate the Natchitoches¬† design.

The next lab in which we explored pottery was back down in the lab. Dr. Hailey brought some unrefined clay to the lab and we processed a little of it. I took the ferrous inclusions and grounded them into ocher for color, but never used it.We went up to Dr. Gregory’s lab and explored PPOs or Poverty Point Objects–small, fist-sized loess objects found at the Poverty Point site in relation and association with cooking. We attempted to replicate the different PPOs (there are 6 different “classes” of them) and I think I figured out how the melon-type was created. By making a preform oval ball and incising it with a small cane reed the groves of the melon were created. Next, a small twist gave it the look of the artifact I was attempting to replicate. I also attempted to replicate the bar-melon design, which looks like a series of connected rings around a cylinder. By rolling the cylinder between my fingers or using a cane reed an elongated cylinder is created with groves in between. To give it the look of the artifact I smashed each of the ends together and compressed it. I think this may be close to the original technique because there are characteristic smudges made in the clay from this type of compression that are present on both the artifact and my replication.

The subsequent lab saw Dr. Hailey hanging the huge wedge of clay from a cedar tree outside of Kyser Hall to dry it before working it. The clay is a dark grey which is a stark difference from the light yellow color of Dr. Gregory’s clay. I created a tall pinch pot and created a slip from clay and ocher for color. Slip is clay in an aqueous suspension that is used to coat and color pottery. It can be applied in a number of ways but I brushed it on with hand-made cane brushes. We created Cuneiform tablets and Venus figurines on our clay as well.

Overall I feel that through the use of experimental archaeology I have a far better understanding of the entire pottery and ceramic process. By understanding how something is created we can begin to recognize the patterns¬† of those who created them within them. The purpose of archaeology isnt about the material remains of the past, but rather the people. Archaeologists only utilize the connections that exist today–the material remains–to arrive at better understandings of past peoples.

 

Published in: on February 15, 2011 at 3:11 pm  Leave a Comment  

Making Fire

Fire is life. Were it not for this advantage our early ancestors would not have survived, let alone develop the taste for cooked meat that allowed their brains to grow. The creation of fire is a tricky business. Fire is tempermental. Too much oxygen and it dies. Not enough oxygen and it dies. The combustion process is what drives this and this lab explored the ways by which fire could be created.

The most primitive and difficult method is f riction via hand-powered spindle. Using this method, one uses a singular spindle rolled between the palms to twist until combustion happens.

Next is the bow method by which the spindle-spinning is aided through the use of a bow. This creates higher speeds, which creates more friction and heat. I managed to create embers and smoke, but no sustainable combustion.

Published in: on February 15, 2011 at 2:15 pm  Leave a Comment  

Making Tools II – Bone

Bone is surprisingly resilient. Once dried and hardened, it is comparable to some types of stone. In order to create stone tools we used a method called abrasion. Once a suitable piece of bone has been selected, a rock with sufficient grain size is selected. Sedimentary rocks from the silica family, like sandstones, work amazingly well for this–think sandpaper.

I created a bone hook and a bone projectile point by abrasion. The point was 7 cm in length and .5cm wide. It took more than 3 hours to abrade it to the designed thickness and to hone an edge.

Published in: on February 15, 2011 at 2:07 pm  Leave a Comment  

Making Tools

Humans aren’t the only species that are fond of tools. Non-human primates and other mammals, such as otters, use tools for achieving their goals. For the nut-cracking chimpanzees, the skills and mental capacity necessary for using tools as simple in design as two rocks are rather complicated.

Our lab consisted of creating stone tools (lithics) from chert and flint. We used direct percussion and indirect percussion methods to achieve this. We created projectile points, blades, and scrapers.

 

Published in: on February 15, 2011 at 2:02 pm  Leave a Comment