11Enclosure: William Lambert’s Calculation of the United States Capitol’s Longitude from Greenwich, 11 July 1822 (Jefferson Papers)
Calculation of the longitude of the Capitol, in the city of Washington , from Greenwich observatory , in England , from the beginning of the Solar Eclipse of August 27 th 1821 , Examined and revised. ° ′ ″ dec
12To Thomas Jefferson from William Lambert, 4 October 1822 (Jefferson Papers)
The inclosed Table being constructed with great care, and on correct principles, may be usefully applied at the University, or Seminary of learning near Charlottesville. On that supposition, I take the liberty to present it to the President of that Seminary, or such professor as you may think proper. ViU .
13To Thomas Jefferson from William Lambert, 2 December 1822 (Jefferson Papers)
Your communication of the 29 th ult o was received this morning. The Equatorial is an instrument with which I am unacquainted; but if it enables an observer to ascertain the horary angle, or time from noon, with sufficient accuracy; or if it be so Constructed, as to show the true azimuth from the north or south points, and the latitude of the place, together with the Sun’s declination be...
14To Thomas Jefferson from William Lambert, 3 December 1822 (Jefferson Papers)
On a further examination of your communication of the 29 th ult o I observe that you state—“If two persons at two points of the same hemisphere, (as Greenwich and Washington, for example) observe the same celestial phenomenon at the same instant of time, the difference of the times marked by their respective clocks, is the difference of their longitudes, or the distance of their meridians”....
15To Thomas Jefferson from William Lambert, 29 May 1823 (Jefferson Papers)
Since the close of the last session of Congress, I have turned my attention to a strict examination of such parts of my astronomical calculations, given in abstract, as relate to solar eclipses and occultations of fixed Stars by the Moon, by various methods and rules, referring to the equator, as well as to the Ecliptic, that the results contained in the report made in November, 1821, might be...
16To Thomas Jefferson from William Lambert, 6 July 1825 (Jefferson Papers)
The form of the Earth having been ascertained by various experiments in Europe and South America, to be that of an Oblate Spheroid; and it being now admitted, that the ratio of the equatorial diameter to the polar axis is as 320 to 319, the measure of a degree in any latitude, according to that ratio, claims our attention; and the following calculations connected with this subject, are...
17William Lambert to James Madison, 10 March 1829 (Madison Papers)
Several unfavorable circumstances have combined to deprive me of that support which, from an early period of life, I had by employment in the public service. Desirous of establishing a first meridian, and an observatory at the seat of the national government, I pursued that object too far, without success, and by that zeal, have lost every thing else beneficial to me. With habits of industry,...