Figure 1. Photo of the four fragments of a Boyd’s Genuine Porcelain Cap Liner. Photo Credit: Andrew Beaupré

Dr. Andrew R. Beaupré, Station Archeologist, ARAS-UAPB
Artifact of the Month - April 2021

This month’s artifact is a cross-mended glass disc identified as a Boyd’s “Porcelain” canning jar liner. Comprised of 4 shards, the nearly complete artifact is 2.5 inches (63mm) in diameter and 1/8 inch (3.175mm) thick. The profile of the artifact is stepped to allow for an airtight seal to the canning jar. The artifact is embossed with the text, “BOYD’S GENUINE PORCELAIN LINED CAP 16” (Figure 1). A major misnomer associated with the artifact is that it is labeled as if it is made of porcelain; however, the artifact is actually made of a transparent and/or translucent “cloudy” glass categorized by archeologists as opaque white but known colloquially as milk glass (Jones and Sullivan 1985:14). At time of manufacture, the liner would have been fit inside an inexpensive threaded metal cap and rubber O-ring to complete the compound canning jar lid (Figure 2).
By the outset of the American Civil War, commercial canning of fruits and vegetables was commonplace (Cowen 1983:73). Many of these early commercially canned goods were famously tainted, as is often cited as the downfall of the 1845 Franklin Expedition to the Canadian Arctic (Swanston et al. 2018). Parallel to the commercial canning of foodstuffs in metal containers, was the development of home canning in glass jars. In 1854, the now household name of the Mason Company began to manufacture canning jars (Hinson 1996). By the late 1850s, patents concentrated on home canning surpassed those associated with commercial operations in an effort to ensure that the individual household was a center of food preservation (Michaels 2015:22). Historical documentations and archeological evidence indicate that by the 1880s, use of canning jars was synonymous with both urban and rural households as well as small cottage industry outlets such as lumber camps (Howe 2015; Michaels 2015; Cowan 1983; Strasser 1982).
Prior to the invention of the liner, circa 1869, canning jar lids were made either entirely of glass or entirely of metal (Boyd 1869). Until Henry Putnam of Bennington, Vermont invented the modern glass lid and “lighting closure” system in 1882, the glass lids available were expensive to manufacture and not suited to creating an airtight seal (Hinson 1996). Therefore, most people opted for the entirely metal lids that all closely followed Mason’s (1858) patent comprised of zinc metal cap with a rubber sealing ring. While sufficiently cheap, the zinc lid system lacked a buffer between the metal and food, giving the food a “quite perceptible taste” (Boyd 1869). Boyd’s liner system retained the cheap screw-top zinc cap but placed the glass liner between the metal and food, ensuring that only glass ever touched the food (Boyd 1869). Boyd’s design was present in home canning operations through the turn of the twentieth century. Over the term of their manufacture, several different styles of these “porcelain” lid liners were produced by Boyd and other companies.


Figure 2. Boyd’s original sketches of the glass liner and zinc cap from his 1869 patent where A represents the zinc cap and B the inset opaque glass liner.
The artifact of the month is one of at least three canning jar liners recorded from initial testing at an early twentieth century urban domestic site in Little Rock, AR. The Doty-McAlpine House is a circa 1911 bungalow style home located in the Governor’s Mansion Historic District. Regardless of its current gubernatorial neighbor, the house was a lower middle-class abode built and first occupied by Charles L. Doty, a clerk for the Little Rock Railway and Electric Company. From 1918, it was the home of Kenneth McAlpine, an employee of the Beal-Burrow Dry Goods Company (Vandenberg 1998).
The introduction of efficient and safe home canning jar technology, represented here by the Boyd’s lids, “offered availability to a year-round variety of palatable and nutritious foods for everyone” (Michaels 2015:24). Within the context of this urban middle-class backyard, we can infer the homemakers in the Doty and or McAlpine families were expanding their family’s diets perhaps with foods that were first homegrown before being home canned. Additionally, this action of home canning chronicles the shifting domestic production habits and traditions at the turn of the twentieth century.
For more information on early twentieth century artifacts in urban contexts, tune into the Quapaw Quarter Association’s April Preservation Conversation Archeology in Your Backyard: Discoveries at the Doty-McAlpine House.

Materials: Glass
Dimensions: 2.5 inches (63mm) in diameter and 1/8 inch (3.175mm) thick
Age Estimate:  Post-1902 (1869 patent)

References Cited
Boyd, Lewis R.
1869    Preventing Corrosion to Metallic Caps. US Patent No. 88,439. U.S. Patent & Trademark Office.
Cowan, Ruth Schwartz
1983    More Work for Mother: The Ironies of Household Technology from the Open Hearth to the Microwave. Basic Books Inc, New York.
Hinson, David
1996    A Primer on Fruit Jars. Bottles and Extras: The Official Publication of the Federation of Historic Bottle Collectors 6(6).
Howe, Aaron
2015    “Men of Good Timber”: An Archaeological Investigation of Labor in Michigan’s Upper Peninsula. Master's Thesis, Department of Anthropology, Western Michigan University, Kalamazoo, MI.
Jones, Olive, and Catherine Sullivan
1989    The Parks Canada Glass Glossary for the Description of Containers, Tableware, Flat Glass, and Closures. Revised Edition. National Historic Parks and Sites Branch, Parks Canada, Environment Canada. Ottawa, Ontario.
Mason, John Landis
1858    Improvement in Screw-neck Bottles. US Patent No. 22,186. U.S. Patent & Trademark Office.
Michaels, Jayne Ann
2015    Canning Jars and Patterns of Canning Behavior: A Study of Households on the Hector Backbone, New York, 1850–1940. Master's Thesis, Department of Anthropology, Western Michigan University, Kalamazoo, MI.
Strasser, Susan
1982    Never Done: A History of American Housework. Random House, New York.
Swanston, Treena, Tamara L. Varney, Madalena Kozachuk, Sanjukta Choudhury, Brian Bewer, Ian Coulthard, Anne Keenleyside, Andrew Nelson, Ronald R. Martin, Douglas R. Stenton, and David M. L. Cooper
2018    Franklin Expedition Lead Exposure: New Insights from High Resolution Confocal X-Ray Fluorescence Imaging of Skeletal Microstructure. PlosONE  Published: August 23, 2018 https://doi.org/10.1371/journal.pone.0202983
1998    Doty-McAlpine House, PU1167. Arkansas Architectural Resources Form. Arkansas Historic Preservation Program. Little Rock, AR.

Artifact of the Month Series

A first principle of archeology is that the significance of artifacts depends upon documented information about the context of their discovery. At what site was the artifact found? Can we figure out the age of the artifact? Where was it found in relation to site features (houses, trash deposits, activity areas, etc.) and the distribution of other artifacts? Only with knowledge of those facts can we assess further information about the manufacture and use of artifacts, and their role in other spheres of activity such as social organization, trade and exchange, and religious practice.
In this series, we feature select artifacts that are extraordinary both for the context of their discovery and for their unique qualities that contribute exceptionally important information about Arkansas culture and history. New artifacts will be added monthly. Find the list of artifacts here.