In view of the Conference’s sub-theme of “sites and geographies of knowledge-production and knowledge-exchange,” I offer the following paper and presentation: Title: “It Would Have Been Thought Chimerical”: Testing First-Generation Steamboats, Water by Water When American inventor Robert Fulton successfully ran his North River Steam Boat as a regular passenger service along the Hudson River in 1807, he demonstrated that it was possible for humans to alter artificially where they were, and when they were there, to practical effect. No other invention had yet accomplished such a thing, making “steamboats” the first high technology in history. But Fulton’s initial success was limited to the Hudson River. It remained to be seen whether these fragile contraptions could be employed successfully on other bodies of water. This presentation will provide a descriptive analysis of how the first generation of steamboat entrepreneurs rapidly and methodically tested (or not!) this first high technology on: —rivers; —canals; —lakes; —bays; —sounds; —and finally the ocean. Chronologically, the paper will cover the period from 1807 to the early 1820s, which can be considered the timeframe for the first generation of steam-powered vessels. The presentation also will show why steam-powered vessels should be considered the first high technology, and how this new definition of the term can be used to fundamentally alter the way we view the history of technology.