of the tenth chapter Copernicus declares: "I do not
hesitate to defend the proposition that the earth, accompanied by the
moon, moves around the sun;" while the wording of this proposition had
to be changed so as to substitute the term "admit" for "defend." The
title of the eleventh chapter, "Demonstration of the Triple Movement
of the Earth," was modified to read as follows: "The Hypothesis of the
Triple Movement of the Earth, and the Reasons Therefor." The title of
the twentieth chapter of the fourth book originally read: "On the Size
of the Three Stars [_Sidera_], the sun, the moon, and the earth." The
word "stars" was removed from this title, the earth not being
considered as a star. The concluding words of {38} the tenth chapter
of the first book, "So great is the magnificent work of the Omnipotent
Artificer," had to be cancelled, because they expressed an assurance
of the truth of his system not warranted by knowledge. With these few
unimportant changes, any one might read and study Copernicus's work
with perfect freedom.

Traditions to the contrary notwithstanding, Galileo, because of the
friendship and encouragement of the churchmen in Italy, had been
placed in conditions eminently suited for study and investigation.
Several popes and a number of prominent ecclesiastics were his
constant friends and patrons. The perpetual secretary of the Paris
Academy of Sciences, M. Bertrand, himself a great mathematician and
historian, declares that the long life of Galileo was one of the most
enviable that is recorded in the history of science. "The tale of his
misfortunes has confirmed the triumph of the truth for which he
suffered. Let us tell the whole truth. This great lesson was learned
without any profound sorrow to Galileo; and his long life, considered
as a whole, was one of the most serene and enviable in the history of
science."

Copernicus, like Galileo, had clerical friends to thank for an
environment that proved the greatest possible aid to his scientific
work. His position as Canon of the Cathedral of Frauenburg provided
him with learned leisure, while his clerical friends took just enough
interest in his investigations and the preliminary {39} announcements
of his discoveries to make his pursuit of astronomical studies to some
definite conclusion a worthy aim in life. It was this assistance that
enabled him to publish his book eventually and bring his great theory
before the world.

Copernicus, far from ha