Philada. April 29th. 1808
A balance of 125 cents has long remained in my hands for the purchase of a Nautical Almanac for the year 1810, which I now send you.
That for 1811 Mr. Garnett will soon put to press, with sundry improvements; Particularly, the moon’s right ascension will be calculated to hours, minutes & seconds of time, as that of the sun & stars has usually been. The moon’s passage over the meridian will also be calculated to hours minutes & seconds; and thus the problems for computing the time from the moon’s altitude, & vice versa, will be rendered much more easy than at present.
The demand for the American ephemeris greatly increases; so that in future, very few, it is probable, will be imported from Europe.
I have the honour to be with sentiments of the greatest respect & esteem your obedient faithful servant
DLC: Papers of Thomas Jefferson.