Image ID: SIL-SIL28-090-05
Cite this: Verne, Jules. 1874. From the Earth to the Moon : direct in ninety-seven hours and twenty minutes, and a trip round it.,New York, Scribner, Armstrong.
Supplied Caption: Admirals Rodman and Dahlgren were two American inventors who perfected heavy cannon design. The tapered barrel reduced the amount of iron required for the same range.
Original Caption: The Rodman Columbiad