At a later period records called ephemerides were kept by order of the emperor; these were much used by the Scriptores Historiae Augustae (see Augustan History).
Written in 1766, it appeared in 1769-1770 in Dupont's journal, the Ephemerides du citoyen, and was published separately in 1776.
The ocean separating Europe from he was dependent upon dead reckoning, for although various methods for determining a longitude were known, the available astronomical ephemerides were not trustworthy, and errors of 30 in longitude were by no means rare.
Such tables are used in the offices of the national Ephemerides to construct ephemerides of the several planets, showing their exact positions in the sky from day to day.
The Ephemerides litterariae (1686) came out at Hamburg in Latin and French.
In July 1628 Kepler accordingly arrived with his family at Sagan in Silesia, where he applied himself to the printing of his ephemerides up to the year 1636, and whence he issued, in 1629, a Notice to the Curious in Things Celestial, warning astronomers of approaching transits.
Of his Ephemerides (1755) practical rules for the employment of the lunar method of longitudes, proposing in his additions to Pierre Bouguer's Traite de Navigation (1760) the model of a nautical almanac.
To this school he rendered valuable service by several pamphlets on financial questions, and numerous articles representing and advocating its views in a popular style in the Journal de l'agriculture, du commerce, et des finances, and the Ephemerides du citoyen, of which he was successively editor.
He also published Narratio de Libris Revolutionum Copernici (Gedenum, 1540), which was subsequently added to editions of Copernicus's works; and Ephemerides until 1551, which were founded on the Copernican doctrines.
For the sake of the survey an observatory was established at Altona, and Schumacher resided there permanently, chiefly occupied with the publication of Ephemerides (11 parts, 1822-1832) and of the journal Astronomische Nachrichten, of which he edited thirtyone volumes.