Fowler’s Patent Model of a Furnace Steam Boiler - ca 1856

Fowler’s Patent Model of a Furnace Steam Boiler - ca 1856

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This model was filed with the application to the U.S. Patent Office for Patent Number 15,803 issued to David H. Fowler of New Orleans, Louisiana on September 30, 1856. Mr. Fowler’s patent was for a new design for a boiler with both internal and external flues. The goal of the two flues was to increase the amount of boiler surface area exposed to the hot combustion gases from the furnace. His design called for a central boiler that was mounted above the furnace. The three supporting legs for the boiler surrounded the furnace and were tubes that allowed the introduction of water into the boiler via the legs. The internal flue passed through the center of the boiler and was surrounded by the water. Combustion gases flowed upward through this flue, transferring heat to the water. The external flue was implemented via a four inch space between the boiler’s side and the surrounding brickwork. This space ran around the entire circumference of the boiler. This allowed a portion of hot combustion gases to also heat the external wall of the boiler, significantly increasing the surface area of boiler metal being exposed to the gases. The external flue was capped at the top of the brickwork, and horizontal openings were provided at regular intervals around the circumference which communicated with the external flue. The chimney was located above the external flue, and a separate pipe connected the internal flue to the external. In 1861 Mr. Fowler advertised as a Steam Boiler Manufacturer in New Orleans. Research of available trade literature and other sources has not revealed any additional commercial use that may have made use of Mr. Fowler’s invention.
The patent model is constructed of unpainted tinplate. It illustrates the central boiler and its internal and external flues as well as the brickwork surrounding the boiler. The aperture at the top for the external flue is present. The furnace door is modelled as are example apertures in the brickwork for ashes to be removed from the external flue. At the bottom of the boiler a single valve or cock for the introduction of water into the boiler via its three supporting legs is modelled. Diagrams showing the complete design can be found in the patent document online and are helpful in terms of understanding the orientation of the boiler and the surrounding brickwork (
Currently not on view
Object Name
patent model, furnace, steam boiler
Object Type
Patent Model
date made
ca 1856
patent date
Fowler, David H.
associated place
United States: Louisiana, New Orleans
overall: 9 7/8 in x 4 3/4 in x 5 1/2 in; 25.0825 cm x 12.065 cm x 13.97 cm
ID Number
catalog number
accession number
patent number
Credit Line
Gift of Raymond F. OReilly, Valley Stream, New York
Patent Models
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Work and Industry: Mechanical and Civil Engineering
Patent Models
Engineering, Building, and Architecture
Data Source
National Museum of American History
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