The Forge and the Foundry

A portion of a map showing the Colt Armory with its Double H Formation
The Colt Armory Complex in 1877 in a map drawn and published by  O.H. Bailey & Co.

Image: Connecticut State Library

After the failure of the Paterson Arms Company, Samuel Colt was more determined to fulfill his dream of opening and operating a successful firearms company. In the early 1850s Colt purchased land in Hartford’s South Meadows, the area later known as Coltsville. It was here the Samuel built what became his most successful business: Colt’s Patent Firearms Manufacturing Company.

Looking at historic maps and photos note the distinct ‘Double H’ design of the complex. The first H, when built, was comprised of the East Armory, the Forge and Foundry buildings and the “spine” connecting the two, with the later west H being built in the 1860s. The design was economical as the H shape provided more floor space than a square and allowed for more natural light as the buildings were narrower and the large bays of windows provided adequate light during the day.
The Forge Shop and Foundry Shop buildings played an essential role in the development of Colt’s Patent Firearms Manufacturing Company; without these two buildings the firearms Samuel made would never exist. The Forge and Foundry shops, buildings 8 and 10 respectively, were built beginning in the early 1850s and completed by 1855; neither burned down in the fire of 1864 which destroyed most of the Colt complex. While similar in design they each had parallel, yet distinct functions. In building 8, the Forge Shop, workers heated and shaped metal with hammers, while in building 10, the Foundry Shop, workers melted metals and created pieces by casting them.
A black and white sketch of the inside of a building where men are working at machines.
A drawing of the Forge Shop, Building 8, from 1857.

Image: The United States Magazine, Vol.IV (Jan. to June 1857)

The Forge and Foundry buildings are prime examples of advanced design in early Industrial America,each built using concepts of adaptation and efficiency. Both were built with large windows to allow ample light for ease of work. These large, open facilities were easily modified to suit the different needs of firearm manufacturing and allow for the addition of new machinery. Partitions could, and were put up, at various times creating small rooms for specific tasks or for sub-contractors who rented the space. The overall design of the buildings allowed for swift economical reorganization.

Along with the visible advances, the buildings also hold a secret-they were built with an internal flue system used to eliminate the cinders and smoke within the buildings. Connected to the furnaces and hidden in the walls were flues which connected to horizontal ducts running though the building which channeled the smoke to a central chimney, located near the storehouse. It is likely that a steam powered exhaust fan ran at the bottom of the chimney to help move the fumes out of the building.


“Along each side rage stacks double-covered forges-the blasts for which, entering and discharging through flues in the walls, carry off the smoke and gases. Here, for the first time in our life were in blacksmith shop in full operation, yet free from smoke and cinders, and with a pure atmosphere.” -United States Magazine 1857, (Pg. 234)

Connecting the Forge Shop and Foundry Shop buildings was a "spine" building that served numerous functions, but was primarily used as a store house. This building allowed for ease of access for materials, and for movement between buildings through exterior passageways. The spine was extended with the addition of the West Armory during the 1860s, but it was completely demolished in 1947, leaving the now visible gap between the two buildings

A building made of brownstone that has broken windows. The City of Hartford is in the background.
The exterior of Building 8 in 2022.

Photo: NPS/Beekman

Building 8, when looking straight on at the East Armory is the brownstone building to the left of the Blue Dome in front of the North Armory (now an apartment complex). When built, it followed the same open fashion as Building 10, but there were two small enclosures at the South end of the building near the store house which housed a tool room and an inspector’s room. These two rooms were placed on either side of a small passageway that entered the storeroom. As the Forge Shop building, hearths were built against every other pier which were connected to the hidden masonry shafts built into the wall. By 1885 forging had moved to the wing west of Building 10 and was replaced by an Iron Foundry. By this time an engine shed, and copula had been added as well. Before the closure of the site the building also was used for woodworking.
Interior of Foundry Building with exposed beams and brick walls
The interior of Building 10

Photo: NPS/O'Maxfield

Building 10, in looking at the East Armory it is the brownstone building to the right of the Blue Dome. Built originally as a foundry the building served many purposes over time. During its initial construction an annealing room was built on the North End adjacent to the iron foundry. By 1857 the building was divided by multiple partitions creating different sections for the annealing room, iron foundry, and a brass foundry. By 1861 the annealing room was used for polishing and in 1885 most of the heating operations were gone and the space was devoted to polishing with a small section at the South end remaining as the brass foundry. Before 1909 the finishing space had expanded into what was previously the store house and the brass foundry had been expanded. Building 10 also served as a sheet metal building and a tin shop before the closure of the site.
brick buildings with a blue onion dome
The Forge and Foundry flank the East Armory and Blue Onion Dome

Photo: NPS/Beekman

The Forge and Foundry shops buildings were the heart of the operations at Colt's Patent Firearms Manufacturing Company. While the complex grew and relocated over time, the original buildings continued to house operations essential for firearms development. Soon these buildings will once again be the heart and soul of the site as the future location of the Coltsville National Historical Park visitor center.
artist rendering of Coltsville NHP with brick building with visitor signs and a school bus dropping off outlines images of students
Artist rendition of Coltsville National Historical Park

Image: JCJ Architecture

Stay tuned and watch for your opportunities to participate in the development of the visitor experience at Coltsville National Historical Park.

Last updated: April 29, 2022

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Contact Info

Mailing Address:

Coltsville National Historical Park
c/o Springfield Armory National Historic Site
One Armory Square, Suite 2

Springfield, MA 01105


(860) 500-6078

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