Observations astronomiques pour topographie américaine

To : M. Quetelet, Director of the Royal Observatory of Brussels
Washington, May 31st 1847
Sir,
Being now engaged, with a corps of Officers of the U.S. Topographical Engineers attached to the Commission of Boundary under the Treaty of Washington, of 1842, in computing the longitude of several very important points along that line of Boundary from observations made by us of the transits of the Moon's bright limb, and of the so called moon culminating stars, I am very desirous to obtain, as far as practicable, any corresponding observations that may have been made on the same days, at the principal European Observatories, and particularly at Brussels.
The within printed catalogue contains

the stars observed by us in connection with the Moon's bright limb, for each date therein set down. At will be esteemed a particular favor by our Government, and by me personally, if you will have the kindness to fill the columns headed « Observed A.R. » with all the corresponding observations, for each date, in the years 1840, 1841, 1844 & 1845, that may have been made at Brussels, and then return the Catalogue to me at this place, through Mr CLEMSON, the U.S. Chargé d'affaires at Brussels, who will forward it to this Government.
I will also ask the favor of you to have the table of Observed Right Ascensions of the Moon's bright limb, at the end of the Catalogue filled as far as may practicable,

from the Brussels observations.
I beg leave to present through you, to the Royal Academy of Sciences & Belles Lettres, and also to the Royal Observatory, of Brussels, for their Libraries, the accompanying copies of maps, as thereon marked & directed.
With profound respect, I have the honor to the very respectfully,
Your obed[ien]t servan. Serv[an]t,
[signé] J.D. Graham