Some confusion has existed concerning Eli Whitney's patent for the cotton gin and the texts of the papers relating to the patent. Mirsky and Nevins 1 refer to the destruction of Whitney's papers in 1795 and the destruction of the Patent Office records in 1836, describe copies of a detailed description of the gin and of a condensed version, and indicate that the drawings are missing; other than copying the short description in an appendix the matter is not pursued further. Lewton 2 gathered a large amount of information concerning existing descriptions, drawings, and models of the original gin and pointed out inconsistencies and gaps. Older writers referred to by Lewton exhibit some misunderstanding and lack of information. Consideration of the requirements of the patent law in Whitney's day, the methods used by the Patent Office in restoring records lost by the fire of 1836, and study of existing papers will resolve most if not all of the confusion and discrepancies. This is attempted in the present note, which is limited to identifying the texts of the papers and showing the sources of a recent Patent Office publication. In August of 1959 the United States Patent Office published for the first time the specification of the patent issued to Eli Whitney for his invention of the cotton gin, together with a copy of the original patent drawing. The patent grant itself was also included in the publication. A patent is a grant by the government of certain exclusive rights to the inventor; a physical document granting these rights is made out, signed, sealed, and delivered to the inventor. The form and content of this patent document have varied in different periods, as have the requirements and procedures for obtaining a patent.3 Whitney's patent was issued under the Patent Act of February 21, 1793,4 which replaced the first United States patent act, of April 10, 1790. There was no Patent Office, the business of issuing patents being handled in the office of the Secretary of State. In order to receive a patent the statute required the following of the inventor: (1) A petition to the Secretary of State; this was merely a formal request for a patent. (2) An oath or affirmation that he believed himself to be the true inventor.