McAvoys Patent Model of a Heat Regulator for Hot Water Apparatus ca 1869. This model was filed with the application to the Patent Office for Patent Number 93,104 issued to Hugh L. McAvoy of Baltimore, Maryland on July 27, 1869.

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Size: 1294px × 1931px
Photo credit: © SBS Eclectic Images / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: engineering, industry, work