Here follows Chapter 2 of the second part of this treatise

The second part is the particular discourse on the comet appearing.

In the year of our Lord fourteen hundred and seventy-

two.

PREFACE Chapter 1 23

1472

22 On the opinions of certain prognosticators concerning the present comet.
23 On the consolations upon which the significations of the comet are founded.
24 On the motion of the comet. 26 On the motion of its tail.
25 On the distance of the comet from the earth. 28 On the magnitude of the comet.
27 On the length of the tail. 30 On the knowledge of the nature and property of the comet a posteriori from its motion, figure, and color. 31
32 On the knowledge of its nature and property a priori from the configuration of the stars.
33 On the general significations of the comet. 34 On mortality from disease.
35 On mortality by the sword and the shedding of blood.
36 On those to whom adverse fortune is threatened.
37 On those to whom prosperous fortune winks.
38 On the special significations of the comet and firstly on the deprivation of rights and privileges.
39 On new customs and ordinances.
40 A summary of the signification of the comet. 21 On the morals of men.

ON THE KINDS OF COMETS Chapter 1

I say, therefore, that there are generally two kinds of comets. One which has hair all around it similarly, and of this there are four species, and they are properly called "comets," though Hali calls them "lords of hair." The other, however, which has rays and filaments extended in length like a tail, of which there are also five species, which Hali calls "lords of the earth," but Aristotle calls "pogonias" bearded ones. In these words: "Whatever has been exhaled, if it is figured all around similarly, it is a comet; but if it is extended in length, it is called a pogonias."

ON THE GENERATION OF COMETS

2 The universal generation of these occurs mostly when the earth is constrained by some celestial property and its pores are constricted. Not by a constriction such as frost causes, but by a retentive power, so that those things which are being thinned and altered in its depths by the action of the stars cannot be exhaled copiously from the earth. This property is ascribed more to Saturn, especially when it is in earth signs. When this property happens, the earth is dissolved by a celestial property coming upon it, which opens the pores of the earth. Then a free exit will open for those things which, as mentioned, have been digested in the depths of the earth by the action of the stars and collected copiously at a suitable time. This property of opening is largely ascribed by authors to Mars; for this reason, all astrologers have opined that the appearances of comets do not occur without Mars. I say, moreover, that Mars is not always the efficient cause, such that it digests and alters this material, but that it is always the cause of promoting and removing what hinders the exhalation, just as Saturn is the cause of the act of retention and gathering. As Saturn leaves the place where it dominated over the earth, and Mars follows it, applying itself to it in an airy place, especially when it is almubtas a technical term in astrology for a dominant planet in a chart