ually to all the
planets, but the proof of this, as well as the reason underlying the
laws, was only given by Newton, who approached the subject from a
totally different standpoint.

This commentary on Mars was published in 1609, the year of the invention
of the telescope, and Kepler petitioned the Emperor for further funds to
enable him to complete the study of the other planets, but once more
there was delay; in 1612 Rudolph died, and his brother Matthias who
succeeded him, cared very little for astronomy or even astrology, though
Kepler was reappointed to his post of Imperial Mathematician. He left
Prague to take up a permanent professorship at the University of Linz.
His own account of the circumstances is gloomy enough. He says, "In the
first place I could get no money from the Court, and my wife, who had
for a long time been suffering from low spirits and despondency, was
taken violently ill towards the end of 1610, with the Hungarian fever,
epilepsy and phrenitis. She was scarcely convalescent when all my three
children were at once attacked with smallpox. Leopold with his army
occupied the town beyond the river just as I lost the dearest of my
sons, him whose nativity you will find in my book on the new star. The
town on this side of the river where I lived was harassed by the
Bohemian troops, whose new levies were insubordinate and insolent; to
complete the whole, the Austrian army brought the plague with them into
the city. I went into Austria and endeavoured to procure the situation
which I now hold. Returning in June, I found my wife in a decline from
her grief at the death of her son, and on the eve of an infectious
fever, and I lost her also within eleven days of my return. Then came
fresh annoyance, of course, and her fortune was to be divided with my
step-sisters. The Emperor Rudolph would not agree to my departure; vain
hopes were given me of being paid from Saxony; my time and money were
wasted together, till on the death of the Emperor in 1612, I was named
again by his successor, and suffered to depart to Linz."

Being thus left a widower with a ten-year-old daughter Susanna, and a
boy Louis of half her age, he looked for a second wife to take charge of
them. He has given an account of eleven ladies whose suitability he
considered. The first, an intimate friend of his first wife, ultimately
declined; one was too old, another an invalid, another too proud of her
birth and quarterings, another could do