entury was Father De Vico,
whose determination of the rotation period of Venus and the
inclination of its axis was considered so exhaustive that it was not
questioned for half a century. He also measured the eccentric position
of Saturn in his rings and observed the motions of the two inner moons
of this planet which had not been seen before this time except by
Herschel. Father De Vico also discovered eight comets, one of them
being the well-known comet with a period of rotation of five and a
half years which bears his name. Father De Vico and Father Secchi were
driven from Rome by the Revolution of 1848, but were brought back to
continue their work just as soon as it was possible. In the meantime
they continued to be personal friends of successive Popes, encouraged
in every way, aided in their work and looked upon as ornaments of the
Church. They were thoroughly respected by their Order and there was
never the slightest question of any possibility of all their studies
in science and all their profound investigation of the deepest
scientific subjects disturbing their faith in any way.

One of the well-known contributors to astronomy during the nineteenth
century was Father Benedict Sestini, who for his mathematical ability
was appointed assistant to Father De Vico of the Roman Observatory. He
was banished from Rome with his brother Jesuits by the Revolution of
1848, and taught at Georgetown College, Washington, D. C, for many
years. His principal work is his catalogue of star colors, published
in the Memoirs of the Roman College, 1845-47. He had very keen vision
and fine skill with the brush, so that his catalogue, which embodies
the entire B.A.C. Star Catalogue, from the North Pole to thirty
degrees south of the equator, will be invaluable for deciding the
question {482} whether there are stars variable in color. He made a
series of sunspot drawings which were engraved and published as
appendix A of the United States Naval Observatory volume for 1847,
printed in 1853. He was the teacher of mathematics and astronomy to
the American Jesuit students and wrote a series of text-books for that
purpose.

As we have said, the Italian government suppressed the Roman College,
declaring it State property and this prevented further work in the
observatory there, which had been for nearly half a century under
Father Secchi and Father De Vico, one of the most important centres in
the world of astronomical advance. Beggared by the