tnote 792: _Comptes Rendus_, t. cxii., p. 549.]

[Footnote 793: _Astr. Journ._, Nos. 169, 170]

[Footnote 794: _The Solar Parallax and its Related Constants_,
Washington, 1891.]

[Footnote 795: _Astr. and Astrophysics_, vol. xiii., p. 626.]

CHAPTER VII

_PLANETS AND SATELLITES_

Johann Hieronymus Schroeter was the Herschel of Germany. He did not,
it is true, possess the more brilliant gifts of his rival. Herschel's
piercing discernment, comprehensive intelligence, and inventive
splendour were wanting to him. He was, nevertheless, the founder of
descriptive astronomy in Germany, as Herschel was in England.

Born at Erfurt in 1745, he prosecuted legal studies at Gottingen, and
there imbibed from Kaestner a life-long devotion to science. From the
law, however, he got the means of living, and, what was to the full as
precious to him, the means of observing. Entering the sphere of
Hanoverian officialism in 1788, he settled a few years later at
Lilienthal, near Bremen, as "Oberamtmann," or chief magistrate. Here he
built a small observatory, enriched in 1785 with a seven-foot reflector
by Herschel, then one of the most powerful instruments to be found
anywhere out of England. It was soon surpassed, through his exertions,
by the first-fruits of native industry in that branch. Schrader of Kiel
transferred his workshops to Lilienthal in 1792, and constructed there,
under the superintendence and at the cost of the astronomical
Oberamtmann, a thirteen-foot reflector, declared by Lalande to be the
finest telescope in existence, and one twenty-seven feet in focal
length, probably as inferior to its predecessor in real efficiency as it
was superior in size.

Thus, with instruments of gradually increasing power, Schroeter studied
during thirty-four years the topography of the moon and planets. The
field was then almost untrodden; he had but few and casual predecessors,
and has since had no equal in the sustained and concentrated patience of
his hourly watchings. Both their prolixity and their enthusiasm are
faithfully reflected in his various treatises. Yet the one may be
pardoned for the sake of the other, especially when it is remembered
that he struck out a substantially new line, and that one of the main
lines of future advance. Moreover, his infectious zeal communicated
itself; he set the example of observing when there was scarcely an
observer in Germany;