21. According to the Chaldaeans.

The Chaldaean method involves a sequence, simple, to be sure, and more plausible, though not so self-sufficient with respect to the government of the triangles and the disposition of quantity, so that, nevertheless, one could easily understand them even without a diagram. For in the first triplicity, Aries, Leo, and Sagittarius, which has with them the same division by signs as with the Egyptians, the lord of the triplicity, Jupiter, is the first to receive terms, then the lord of the next triangle, Venus, next the lord of the triangle of Gemini, Saturn, and Mercury, and finally the lord of the remaining triplicity, Mars. In the second triplicity, Taurus, Virgo, and Capricorn, which again has the same division by signs, Venus is first, then Saturn, and again Mercury, after these Mars, and finally Jupiter. This arrangement in general is observed also in the remaining two triplicities. Of the two lords of the same triplicity, however, Saturn and Mercury, by day Saturn takes the first place in the order of ownership, by night Mercury. The number assigned to each is also a simple matter. For in order that the number of terms of each planet may be less by One degree than the preceding, to correspond with the descending order in which first place is assigned, they always assign 8° to the first, 7° to the second, 6° to the third, 5° to the fourth, and 4° to the last; thus the 30° of a sign is made up. The sum of the number of degrees thus assigned to Saturn is 78 by day and 66 by night, to Jupiter 72, to Mars 69, to Venus 75, to Mercury 66 by day and 78 by night; the total is 360 degrees.
Now of these terms those which are constituted by the Egyptian method are, as we said, more worthy of credence, both because in the form in which they have been collected by the Egyptian writers they have for their utility been deemed worthy of record, and because for the most part the degrees of these terms are consistent with the nativities which have been recorded by them as examples. As these very writers, however, nowhere explain their arrangement or their number, their failure to agree in an account of the system might well become an object of suspicion and a subject for criticism. Recently. however, we have come upon an ancient manuscript, much damaged, which contains a natural and consistent explanation of their order and number, and at the same time the degrees reported in the aforesaid nativities and the numbers given in the summations were found to agree with the tabulation of the ancients. The hook was very lengthy in expression and excessive in demonstration, and its damaged state made it hard to read, so that I could barely gain an idea of its general purport; that too, in spite of the help offered by the tabulations of the terms, better preserved because they were placed at the end of the book. At any rate the general scheme of assignment of the terms is as follows. For their arrangement within each sign, the exaltations, triplicates, and houses are taken into consideration. For, generally speaking, the star that has two rulerships of this sort in the same sign is placed first, even though it may be maleficent. But wherever this condition does not exist, the maleficent planets are always put last, and the lords of the exaltation first, the lords of the triplicity next, and then those of the house, following the order of the signs. And again in order, those that have two lordships each are preferred to the one which has but one in the same sign. Since terms are not allotted to the luminaries, however, Cancer and Leo, the houses of the sun and moon, are assigned to the maleficent planets because they were deprived of their share in the order, Cancer to Mars and Leo to Saturn; in these the order appropriate to them is preserved. As for the number of the terms, when no star is found with two prerogatives, either in the sign itself or in those which follow it within the quadrant, there are assigned to each of the beneficent planets, that is, to Jupiter and Venus, 7° ; to the maleficent, Saturn and Mars, 5° each; and to Mercury, which is common, 6°; so that the total is 30°. But since some always have two prerogatives for Venus alone becomes the ruler of the triplicity of Taurus, since the moon does not participate in the terms there is given to each one of those in such condition, whether it be in the same sign or in the following signs within the quadrant, one extra degree; these were marked with dots. But the degrees added for double prerogatives are taken away from the others, which have but one, and, generally speaking, from Saturn and Jupiter because of their slower motion. these terms is as follows:

Terms according to Ptolemy.

Aries : Jupiter = 6; Venus = 8; Merkur = 7; Mars = 5; Saturn = 4;

Taurus : Venus = 8; Merkur = 7; Jupiter = 7; Saturn = 2; Mars = 6;

Gemini : Merkur = 7; Jupiter = 6; Venus = 7; Mars = 6; Saturn = 4;

Cancer : Mars = 6; Jupiter = 7; Merkur = 7; Venus = 7; Saturn = 3;

Leo : Jupiter = 6; Merkur = 7; Saturn = 6; Venus = 6; Mars = 5;

Virgo : Merkur = 7; Venus = 6; Jupiter = ; Saturn = 6; Mars = 6;

Libra : Saturn = 6; Venus = 5; Merkur = 5; Jupiter = 8; Mars = 6;

Scorpio : Mars = 6; Venus = 7 ; Jupiter = 8; Merkur = 6; Saturn = 3;

Sagittarius : Jupiter = 8; Venus = 6; Merkur = 5; Saturn = 6; Mars = 5;

Capricornus : Venus = 6; Merkur = 6; Jupiter = 7; Saturn = 6; Mars = 5;

Aquarius : Saturn = 6; Merkur = 6; Venus = 8; Jupiter = 5; Mars = 5;

Pisces : Venus = 8; Jupiter = 6; Merkur = 6; Mars = 5; Saturn = 5;

Ptolemy's Tetrabiblos

Main Library