Autograph letter signed, to U.S. Coast Survey Superintendent Alexander Dallas Bache, sending him an article she has written about the Coast Survey, after spending the preceding summer at Mt. Independence, Maine, using a zenith sector and the zenith telescope to make latitude and longitude observations for the great field triangulation survey

Nantucket, 1851. 1-1/4pp, on a folded 4to sheet. Minor staining at bottom left. 1-1/4pp, on a folded 4to sheet. Sending the Proofs of her First Academic Paper. "On the evening of October 1, 1847, while using a small telescope on the roof of the family home, Maria Mitchell (1818-1889) spotted a comet where one had not been before. Word of this achievement spread quickly through the scientific community. The American Journal of Science declared her 'the first American entitled to the honor of the original discovery of a comet.' Some months later, thanks in part to Harvard College President Edward Everett, she received a gold medal from the King of Denmark, thus becoming one of the first Americans to win any sort of medal for science. She was unanimously elected an honorary member of the American Academy of Arts and Sciences, the first (and for many years the only) woman so honored" (https://siarchives.si.edu/blog/maria-mitchell-and-smithsonian).

Just two years after her comet discovery, Mitchell accepted a computing and field research position for the U.S. Coast Survey undertaken at the U.S. Nautical Almanac Office. Her work consisted of tracking the movements of the planets -- particularly Venus -- and compiling tables of their positions to assist sailors in navigation. That summer, she was invited by Bache, who had been an mentor and indefatigable supporter, to participate in the astronomical party at Mount Independence, Maine as part of the U.S. Coast Survey. "That summer, she always felt, was enchanted. Long afterward the memory of the far vistas of the rocky Maine coast came to cheer her. In dark moments she remembered nights on the mountain top where they made latitude and longitude observations for the great field triangulation survey from Maine to North Carolina. Yet, most of all, she remembered the kindly, good-natured and great man who had made it all possible" (Helen Wright, Sweeper in the Sky [New York: 1949]).

Mitchell's work for the survey constituted among the first, if not the first, examples of a woman being employed by the federal government in a professional academic capacity. Following her return to Nantucket, Mitchell authored a detailed article on the work of the survey and the use of zenith instruments, which would be published in the January 1852 issue of the Christian Examiner. It would be her first detailed academic paper.

The present letter to Bache sends him the proofs of her article for his comments. She writes: "I send you such sheets of my article, as it seems to me necessary that you should see. Say what you think as you would to a third person. I hope that in my efforts to get up with the subject I have developed some muscles - if I have, it is reward enough for my labour; I have rather enjoyed the new reading which it has led me into. In my conclusion, on a sheet which I don't send, I say that the memoirs presented at the meetings of scientific bodies by officers of the survey who avail themselves of their location for scientific investigation are a consequence of the survey & valuable to the country however little recognized as objects of the appropriation. Is there any harm in that? I know so little of what influences that I can't tell, and even if I was sure of never having a reader, I should be sorry to write what, if read, would influence many. Please skim over and return as soon as possible..."

The article begins by briefly reviewing the history of the survey and its acquisition of instruments, followed by a very detailed description of its trigonometric and geodetic work, with explanation of the relevant mathematics and astronomy and much on the use of a circuit-breaking clock and the determination of both longitude and latitude. Effusive in her praise for Bache and the survey's work, she concludes the lengthy article, asking "Who shall measure that far reaching result, the intellectual and moral good which a government confers on its people, when it awakens an interest in questions of science?"

Letters by Mitchell directly related to her scientific pursuits or her academic articles are very unusual. "The most prominent woman professor ... and the first real 'scientist' since Jane Colden in the 1750s, in that she published at least seven scientific articles, was the astronomer Maria Mitchell, certainly the most important woman scientist in America in the nineteenth century. Her election to a professorship at Vassar College opened a new era for women in American science" (Rossiter, Women Scientists in America I, p. 13).