J.S. Berry Firebrick Pug Mill (18BC89)

The Berry Brick Mill (18BC89) site consists of the archaeological remains associated with the mid to late 19th-century J.S. Berry Firebrick Pug Mill in the Camden Yards area of downtown Baltimore. Baltimore Block #925, in which the site is located, was annexed to the city in 1783. During the first half of the 19th century, very few lots were developed or improved, but tax records indicate that a John W. Berry was operating a brick kiln at Russell and Hamburg Streets as early as 1838. The Berry family’s major brickmaking operations were at that time located elsewhere. It was not until the 1850s that John S. and George Berry moved major operations to Block #925.

An 1851 map of the city depicts only 3 structures within Block #925 (one of which is the brick kiln). But by 1858, John and George Berry had acquired all of Block #925 except for James W. Pawley’s lot (on which he operated a stoneware kiln – see synopsis for 18BC88). By the 1870s, the Berry’s enterprise dominated the entire block. The Pawley property was subdivided and developed into townhomes during the middle and late 19th century. Tax assessment maps for 1876 show that the brickworks occupied the entire section east of Claret Alley, and that John, George, and William Berry controlled approximately 2/3 of the block west of Claret Alley. However, the lots on Russell Street were identified as “unimproved”, indicating that the 1838 brick kiln had been removed. The 1890 Sanborn-Perris Fire Insurance Map of the Berry Brick Works shows that the complex included several unidentified single-story frame structures, two or three kilns (both wood and coal-fired), a brick oven, several single-story brick sheds, a tool house, brick floors, and four clay pits.

The site was first examined archaeologically in 1989 during a Phase I study at Baltimore’s Camden Yards. The survey used a combination of pedestrian survey, the mechanical excavation of 88 test trenches, and the hand excavation of 5 formal test units (apparently 1 X 1 m in size). Two features were identified in Trench 82. These were brick-lined, steam-powered pug mills shown on the 1890 Sanborn Fire Insurance Maps. An additional feature also was exposed within Trench 84: a mortared stone wall positioned parallel to Hamburg Street. The wall was interpreted as the foundation of a late 19th-century rowhouse in this area of the property.

Based on the findings from the Phase I study, Phase III data recovery was recommended. To thoroughly document the horse-drawn pug mill, an area covering approximately 10 X 10 m, was cleared of overlying fill deposits and hand excavated to expose 100% of the wooden superstructure. Once exposed, the wooden mill structure was cleaned and documented through scaled drawing and large-format photography.

Three collapsed trapezoidal wooden structures were documented lying on the mill floor. The impressions of uprights and vertical planking were also noted along the exterior. Precise measurement and comparison of these elements revealed that the intact wooden constructions were collapsed portions of the exterior wall.

The wooden structure identified at 18BC89 represents an isolated remnant to the Berry Brick Company works that occupied this portion of the block from about 1850 to 1890. The Berry operation was relatively large, but not as large as some others in Baltimore, such as Reiers, Russell, and Company. The Berry operation made fire bricks for the Baltimore-Washington market in the period just prior to the development of mass production. The pug mill represents the second of five stages of brick manufacturing: mining, preparation, molding, drying, and firing. The mills, first horse-drawn, then steam powered, and mechanized, were used to mix tempering agents with the raw clays after they had weathered, and before they were molded.

Archaeological investigations indicated that the wooden remains represented the base and sides of a large wooden tub, constructed of pine planks, and resting on a subfloor made of reused oak beams. A mechanism for mixing the raw clay with tempering agents, similar to that shown in patent drawings, would have rested over the central opening in the plank floor. This mechanism would have been powered by a horse or mule hitched to a sweep.

(Edited from the Maryland Historical Trust Synthesis Project)


  • Kuranda, Kathryn, Elizabeth Pena, Suzanne Sanders, Martha R. Williams, David Landon, and Justine Woodard
  • 1992. Archeological and Architectural Investigations at Camden Yards, Baltimore, Maryland 2 vols. R. Christopher Goodwin and Associates, Inc.
  • Sanders, Suzanne, and Martha R. Williams
  • 1998. Archeological Mitigation of the J. S. Berry Brick Mill (18BC88) and Pawley Stoneware Kiln (18BC89), Baltimore, Maryland R. Christopher Goodwin and Associates, Inc.

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