Herschel, [F.] W.
Astronomical observations on the rotations of the planets round their axes, made with a view to determine whether the Earth's diurnal motion is perfectly equable.
London, The Royal Society, 1781. 4to (24.5 x 19.5 cm). 24 pp. (numbered 115-138); two large, foldout plates. Spine with marbled paper cover.
Rare early paper by the German-British astronomer Friedrich Wilhelm - later Frederick William - Herschel (1738-1822) on the revolving motion of the Earth and other planets, in particular Mars and Jupiter. The results he obtained were quite accurate, especially those of Mars. Herschel's famously large telescopes were excellent instruments for this kind of research. A rare original issue of this paper, taken from the Philosophical Transactions for the year 1781 (thus not from the later, abridged edition). Uncut, with the widest possible margins. Some very mild offsetting, but mostly clean, unmarked. In all in very good condition. Houzeau & Lancaster II, p. 610.
