Abraham Lincoln's patent relates to an invention to lift boats over shoals and obstructions in a river. It is the only United States patent ever registered to a President of the United States.Lincoln conceived the idea of inventing a mechanism that would lift a boat over shoals and obstructions when on two different occasions the boat on which he traveled got hung up on obstructions. Documentation of this patent was discovered in 1997.

This device was composed of large bellows attached to the sides of a boat that was expandable due to air chambers. His successful patent application led to his drafting and delivering two lectures on the subject of patents while he was President. Lincoln was at times a patent attorney and was familiar with the patent application process as well as patent lawsuit proceedings. Among his notable patent law experiences was litigation over the mechanical reaper; both he and his future Secretary of War, Edwin Stanton, provided counsel for John Henry Manny.

According to wikipedia