ace much of the essence of Arminianism. The style of
Cassianus is slovenly, and shows no literary polish, but its direct
simplicity is far superior to the rhetorical affectations which
disfigure most of the writings of that age. At the request of Castor,
bishop of Apt, he wrote two monumental and influential treatises on the
monastic life. The _De Institutione Coenobiorum_ (twelve books)
describes the dress, the food, the devotional exercises, the discipline
and the special spiritual dangers of monastic life in the East
(gluttony, unchastity, avarice, anger, gloom, apathy, vanity and pride).
The _Collationes Patrum_, a series of dialogues with the pious fathers
of Egypt, deal with the way in which these dangers (and others, e.g.
demons) may be avoided or overcome. At the desire of Leo (then
archdeacon of Rome) he wrote against Nestorius his _De Incarnatione
Domini_ in seven books.

EDITIONS.--Douay (1616) by Alardus Gazaus, with excellent notes;
Migne's _Patrol. Lat._ vols. xlix. and l.; M. Petschenig in the Vienna
_Corpus Script. Eccles. Lat._ (2 vols., 1886-1888). See A. Harnack,
_History of Dogma_, v. 246 ff., 253 ff.; A. Hoch, _Die Lehre d. Joh.
Cassian von Natur und Gnade_ (Freiburg, 1895); W. Moeller, _History of
the Chr. Church_, i. 368-370.

CASSINI, the name of an Italian family of astronomers, four generations
of whom succeeded each other in official charge of the observatory at
Paris.

GIOVANNI DOMENICO CASSINI (1625-1712), the first of these, was born at
Perinaldo near Nice on the 8th of June 1625. Educated by the Jesuits at
Genoa, he was nominated in 1650 professor of astronomy in the university
of Bologna; he observed and wrote a treatise on the comet of 1652; was
employed by the senate of Bologna as hydraulic engineer; and appointed
by Pope Alexander VII. inspector of fortifications in 1657, and
subsequently director of waterways in the papal states. His
determinations of the rotation-periods of Jupiter, Mars and Venus in
1665-1667 enhanced his fame; and Louis XIV. applied for his services in
1669 at the stately observatory then in course of erection at Paris. The
pope (Clement IX.) reluctantly assented, on the understanding that the
appointment was to be temporary; but it proved to be irrevocable.
Cassini was naturalized as a French subject in 1673, having begun work
at the observatory in September 1671. Between 1671 and 1684 he
discovered four Saturnian satellites, and in 1675 the d