Original patent lithographs and specification sheet for Henry A. Duc, Jr.'s' "Apparatus for Propelling Vessels by Hydraulic Pressure," five pages, 7.75 x 11.5, patented May 24, 1910. The diagrams show multiple views of the apparatus for propulsion of vessels. The specification sheet describes the invention in detail, which comprises a "novel arrangement and construction of rotary turbine actuated pumps for imparting pressure to the currents of water and driving the same with increased power or velocity toward the exit of the channels." In fine condition.
