Beschreibung:

DUNBAR, WILLIAM, Sir, Surveyor General of Natchez District . Manuscript "Account of the Commencement and Progress of the First 18 Miles of the Line of Demarcation...between the Territories of Spain and the United States of America, Concluding with Observations and Remarks on the Country, its Climate, Productions, etc.," in a neat clerical hand, the text incorporating tabular scientific charts, a few corrections in a different hand, n.p., n.d. [New Orleans, 1798]. 71 pages (including six internal blank pages), 4to, 230 x 200mm. (9 x 7 3/4 in.), elaborate calligraphic title-page, contemporary coarse paper wrappers, the "annexed map" noted on page 1 is not present (but there are no evident signs of its removal); brown quarter morocco slipcase . DUNBAR'S SURVEY OF THE U.S.-SPANISH BOUNDARY LINE EAST OF THE MISSISSIPPI A fascinating record of the survey of the boundary between the United States and Spanish territories west of the Mississippi, undertaken by Dunbar at the behest of the Spanish government. In the introduction to his scientific notes and journal, Dunbar explains that the Spanish government had given permission for Dunbar to collaborate with the American Commissioner, Surveyor Andrew Ellicott 26 May 1798: "I arrived at the encampment of the American Commissioner with the necessary instruments, consisting principally of the Astronomical Circle...on the principles of...Mr. Ramsden of London...and an excellent brass sextant on the construction of Hadley..." Dunbar takes pains to explain that he has "...the highest confidence in the scientific knowledge" and "veracity" of the American Commissioner. The daily records of his survey extend from 1 August until 31 August 1798 and narrate in detail the scientific methods employed in the mapping: "15th August...preparations being made for making the observation [of the star Pegasus] with accuracy in the manner following...A copper lantern being prepared...and a candle being placed therein, the lantern was carried in the day time a considerable distance to the East, and the Astronomical Circle being nicely adjusted to the tangent, the open slit of the lantern was placed exactly to coincide with the vertical hair of the Instrument...which might enable the observer to rectify any small error in the position of the instrument. Matters being thus arranged, the Star was seen to pass the Vertical wire of the transit Instrument..." 28 August: "The line having been now carried beyond the point of...the distance of about 18 miles from the River of Mississippi, including the whole of the cultivated lands, I signified to the Spanish Government my intention of retiring from the Line agreeably to the Stipulation which was made at the commencement of this operation, and accordingly I set out on the 31st day of August...On my return home I prepared the foregoing account of the Operations performed...which were transmitted to my Successor Don Stephen Minor, Mayor in the Spanish Service, to be by him forwarded to the Spanish Government at New Orleans..." Dunbar's 37-page appendix, entitled "Notes Taken at my Encampment on the Bluff," is of considerable interest, containing observations and speculations on the topography, vegetation, agriculture and wildlife of the region, occasionally referring to accounts of the early French explorer Le Page Du Pratz. Even the waters of the Mississippi came under Dunbar's scrutiny: "The microscope discovers those waters to contain the same varieties of animalcules which I have often examined in Europe, and many new ones..." He records his observations of panther, black bear, mink, catfish, and the alligator, which "seems to be precisely the same with the crocodile of the Nile, although they do not arrive to so great a magnitude...and I have not known of anyone being attacked in the Water not withstanding the common practice of bathing in the Mississippi..." Trees and fruiting plants of the region are recorded in detail and Dunbar adds a "List of the Most Rema