The first of these in chronological order, bears the date of July 15, 1800. It states briefly that in compliance with the request of a friend in London, Dunbar had prepared certain notes and remarks "made while upon the line of Demarcation." These he sent to Jefferson with a request that after reading he forward them to London. Jefferson, who was then President of the American Philosophical Society and a great patron of science, was so favorably impressed by these notes that instead of forwarding them as directed, he sent them to Dr. Wistar of Philadelphia with a recommendation that Dunbar be elected to membership in the Philosophical Society. On this point Jefferson wrote that he had proposed so many members at different times that he was afraid to add to the number. "Yet," says he, "Dunbar ought to be associated to us. I enclose you a letter with communications of his to Mr. Smith of London which ____will enable you to judge of his degree of science, & therefore, I leave them open for your perusal, & will pray you to seal & send them____to London." Shortly after this Dunbar was elected to membership in this, the most celebrated organization of scientists in the early history of the United States. The fact that only thirteen other Americans were added to this body during the three years from January 1st, 1799 to 1802, gives a proper estimate of the high honor conferred upon Mr. Dunbar. In writing to Dunbar, shortly after this recognition of his scientific attainments, Ellicott says: "If you do justice to your own abilities and observations, you will do credit to the society by your communications." Before considering the character and extent of his subsequent contributions to science, the notes and remarks referred to above demand consideration. These are contained in his report of the survey to his Catholic Majesty,[54] the Spanish copy of which is in the archives at Madrid. Several years ago it was examined by Alexander Everett, who often referred to it as "a document of rare science and accuracy."[55] It consists of two parts. The first treats of the mathematical calculations and the astronomical observations made in locating the 31° of latitude and in surveying the first eighteen miles of the line of demarcation. The remainder consists of notes taken at his encampment on the Bluff, in August, 1798. These treat, for the most part, of the vegetable and animal life to be found along the line of the survey, particularly in the swamp of the Mississippi river.