There are six hundred plates, but the exact number of species figured (which has been computed at six hundred and sixty-one) is not so easily ascertained.
To form a conception of this problem it is to be noted that since the position of the body in space can be computed from the six elements of the orbit at any time we may ideally conceive the coordinates of the body to be algebraically expressed as functions of the six elements and of the time.
The earliest literary papyrus is that known, from the name of its former owner, as the Prisse papyrus, and now preserved at Paris, containing a work composed in the reign of a king of the fifth dynasty, and computed to be itself of the age of upwards of 2500 years B,C. The papyri discovered in Egypt have often been found in tombs, and in the hands, or swathed with the bodies, of mummies.
On the conquest of a country the lands were apportioned by the nishanjis, who first computed the tithe revenueof each village, its population, woods, pasturage, &c.; and divided it into the three classes of fiefs (khas, ziamet and timar), or into vakilf (pious endowments) or pasturage.
We should therefore probably ascribe the work attributed to him in the Hotel Carnavalet (in situ), together with much else executed in various parts of Paris - but now dispersed or destroyed - to a period intervening between the date of his dismissal from the Louvre and his death, which is computed to have taken place between 1564 and 1568, probably at Bologna.