that time leave Germany, giving several reasons, one of
which was that he dreaded the confinement of an island. Later on he
expressed his willingness to go as soon as his Rudolphine Tables were
published, and lecture on them, even in England, if he could not do it
in Germany, and if a good enough salary were forthcoming.
In 1624 he went to Vienna, and managed to extract from the Treasury 6000
florins on account of expenses connected with the Tables, but, instead
of a further grant, was given letters to the States of Swabia, which
owed money to the Imperial treasury. Some of this he succeeded in
collecting, but the Tables were still further delayed by the religious
disturbances then becoming violent. The Jesuits contrived to have
Kepler's library sealed up, and, but for the Imperial protection, would
have imprisoned him also; moreover the peasants revolted and blockaded
Linz. In 1627, however, the long promised Tables, the first to discard
the conventional circular motion, were at last published at Ulm in four
parts. Two of these parts consisted of subsidiary Tables, of logarithms
and other computing devices, another contained Tables of the elements of
the sun, moon, and planets, and the fourth gave the places of a thousand
stars as determined by Tycho, with Tycho's refraction Tables, which had
the peculiarity of using different values for the refraction of the sun,
moon, and stars. From a map prefixed to some copies of the Tables, we
may infer that Kepler was one of the first, if not actually the first,
to suggest the method of determining differences of longitude by
occultations of stars at the moon's limb. In an Appendix, he showed how
his Tables could be used by astrologers for their predictions, saying
"Astronomy is the daughter of Astrology, and this modern Astrology again
is the daughter of Astronomy, bearing something of the lineaments of her
grandmother; and, as I have already said, this foolish daughter,
Astrology, supports her wise but needy mother, Astronomy, from the
profits of a profession not generally considered creditable". There is
no doubt that Kepler strongly resented having to depend so much for his
income on such methods which he certainly did not consider creditable.
It was probably Galileo whose praise of the new Tables induced the Grand
Duke of Tuscany to send Kepler a gold chain soon after their
publication, and we may perhaps regard it as a mark of favour from the
Emperor Ferdinand that he p
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