ded him jocularly of his requiring the sinews of
war to make similar attacks upon the other planets. The Emperor,
however, had more formidable enemies than Jupiter and Saturn, and from
the treasury, which war had exhausted, he found it difficult to supply
the wants of science. While Kepler was thus involved in the miseries of
poverty, misfortunes of every kind filled up the cup of his adversity.
His wife, who had long been the victim of low spirits, was seized,
towards the end of 1610, with fever, epilepsy, and phrenitis, and before
she had completely recovered, all his three children were simultaneously
attacked with the smallpox. His favourite son fell a victim to this
malady, and at the same time Prague was partially occupied by the troops
of Leopold. The part of the city where Kepler resided was harassed by
the Bohemian levies, and, to crown this list of evils, the Austrian
troops introduced the plague into the city.

Sometime afterwards Kepler set out for Austria with the view of
obtaining the professorship of mathematics at Linz, which was now
vacant; but, upon his return in June, he found his wife in a decline,
brought on by grief for the loss of her son, and she was sometime
afterwards seized with an infectious fever, of which she died.

The Emperor Rudolph was unwilling to allow Kepler to quit Prague. He
encouraged him with hopes that the arrears of his salary would be paid
from Saxony; but these hopes were fallacious, and it was not till the
death of Rudolph, in 1612, that Kepler was freed from these distressing
embarrassments.

On the accession of Mathias, Rudolph's brother, Kepler was re-appointed
imperial mathematician, and was allowed to accept the professorship at
Linz. His family now consisted of two children--a daughter, Susannah,
born in 1602, and a son, Louis, born in 1607. His own time was so
completely occupied by his new professorial duties, as well as by his
private studies, that he found it necessary to seek another parent for
his children. For this purpose, he gave a commission to his friends to
look out for him a suitable wife, and, in a long and jocular letter to
Baron Strahlendorf, he has given an amusing account of the different
negotiations which preceded his marriage. The substance of this letter
is so well given by Mr Drinkwater Bethune, that we shall follow his
account of it.

The first of the eleven ladies among whom his inclinations wavered, "was
a widow, an intimate friend of his