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Texas Archaeology Month at the Alamo - Week Three

Tiffany M. Lindley, PhD, RPA, Archaeologist
October 18, 2021

For our third Archaeology Month post, we are going to highlight two different artifacts classes that are frequently encountered at historic sites, like the Alamo: Glass and Metal.

Glass

The origin of glass production is still uncertain but was likely in Mesopotamia or Egypt around 5000 BCE. The first glass may have been an accidental invention that resulted from experimentation with ceramic glazes. Faience was the first glass-like object produced, and it reached full technological development in Egypt.  Faience was made by creating a glaze layer over a silica core. The silica never completely melts, which creates a final product that is an intermediate material between a glaze and true glass.  The first examples of true glass objects come from around 2500 BCE in Syria and around 2200 BCE in Egypt. Glass objects and glass production were brought to the Americas by the Europeans and was not present in Texas until the Spanish arrival.

Glass artifacts can come in many forms: containers, windowpanes, beads and jewelry, and even toys. Like most artifacts, glass artifacts are usually broken when archaeologists find them, but complete artifacts are also recovered. Glass is a great artifact because it can represent various activities and to time periods.

Round glass marble found in excavation
Round glass marble found in excavation
Glass artifacts from Alamo excavations
Light green round glass with a hole in the middle found in excavation
Glass bottle with a metal copy from an excavation
Glass bottle with metal cap recovered from Alamo excavations

Glass bottles can also provide several clues about available technology and popular trends from the time of their production. Some glass bottles are useful in assigning time periods to the context in which they were found. Using physical, manufacturing-related diagnostic features, many bottles can be dated within a range of 10-15 years. The presence of maker’s marks on the base of some glass bottles can provide the name and location of the manufacturer. Time periods can be assigned to some bottles, because some manufacturers produced specific bottles during a certain date range. Maker’s marks could be as simple as a geometric figure, or they may include the initials of the company name.

Look closely at the bottle presented below. At first glance it might appear to be a simple, brown bottle. However this bottle holds a lot of information. The base has a maker’s mark that reads “1905 Paul Jones 18.” The bottle was likely manufactured in  1905 by Paul Jones & Co. and the number 18 likely signifies the mold number. Paul Jones owned several brands in Louisville, Kentucky, including the famous Four Roses whiskey. Looking at the seam visible on the profile and the form of the base, we know this bottle was made using a cup-bottom mold. This bottle exhibits a straight brandy finish (the rim of the bottle), which was common from about 1860-1920.

If you want to learn more about historical bottles visit the Historic Glass Bottle Identification and Information Website.

Brown liquor bottle found in excavation
Base of historical liquor bottle that reads “1905 Paul Jones 18”
Historical liquor bottle recovered from Alamo excavations
Side view of historical liquor bottle found in excavation
Trio of metal chain links fused together from corrosion
Metal chain links that have fused together as a result of corrosion

Metals

Many of the metal artifacts found at archaeological sites are iron, copper, or one of the copper alloys (i.e., brass and bronze). Precious metals like gold and silver are not often encountered in the archaeological record. When metal artifacts are recovered, typically they exhibit very poor preservation. Some of the preservation issues arise from the physical environment. For example, a damp, humid environment will speed up corrosion of metal. Archaeologists sometimes recover metal artifacts that have corroded beyond recognition. Metal artifacts in this region of the United States postdate the arrival of the Spanish.

There are many forms and functional categories for metal artifacts. At the Alamo, one of the most common metal artifacts are iron nails. While a nail might not seem like an important artifact, they have temporally diagnostic technological features. The earliest nails were hand wrought by a blacksmith drawing out large iron bars to a smaller size and then hammering into shape. Hand wrought nails typically are square, although not necessarily perfectly square, in cross section. Hand wrought nails are made individually and as a result have a lot of variability.

In the late 18th century, multiple machines were invented to streamline nail production. One machine, patented by Jacob Perkins, made nails through a process of first cutting the shank with one machine and then heading the nail with a different machine. Later the automated process was refined and the cutting and heading of the nail was done by a single machine. These nails are identifiable by the tapering near the head and, frequently, the irregularity of the head shape.

Hand wrought nails and spikes
Hand wrought nails and spikes from Mission San Sabá; Image accessed at https://www.texasbeyondhistory.net/sansaba/images/R13.html
Set of 4 machine cut nails
Machine cut nails; Image accessed at https://www.urbanremainschicago.com/news-and-events/2018/05/27/meticulously-documenting-19th-century-residential-and-commercial-balloon-frame-iron-nails/

In the late 19th century, wire nails were the most popular type of nail because of their low cost. The wire nail was entirely machine-made and resembles the nails we see today.

At first glance, glass and metal artifacts may seem to be mundane objects with little story to tell. However, they hold clues about the past people who used them. Everyday items, like glass and metal, provide insight into the everyday life of society. By analyzing these types of artifacts archaeologists can glean information about the types of activities that occurred at a site.

Sources:

Lindsey, Bill.
2020 Bottle Dating. In Historic Glass Bottle Identification & Information Website.  Electronic document, accessed October 11, 2021.

Rasmussen, Seth
2012 How Glass Changed the World: The History and Chemistry of Glass from Antiquity to the 13th Century. Springer, Fargo, North Dakota.

Adams, William Hampton
2002 Machine Cut Nails and Wire Nails: American Production and Use for Dating 19th Century and Early 20th Century Sites. Historical Archaeology 36(4):66-88.