Ptolemy's Tetrabiblos · Ptolemy
NUMBER OF THE MODES OF PROROGATION
When the prorogator has been determined as above directed, it is also necessary to take into consideration the two modes of prorogation; one into succeeding signs, under the projection of rays, as it is called; and, when the prorogator may be in an oriental place, that is to say, in any place between the mid-heaven and the ascendant, this mode only is to be used. The other mode extends into signs preceding the prorogator, according to what is called horary proportion[147]; and, in cases when the prorogator may be situated in any place receding from the mid-heaven, or, in other words, between the mid-heaven and the angle of the west, both modes of prorogation are to be adopted. [147] “_Horary proportion._” So the Perugio Latin of 1646; the Greek word, however, is ωριμαιαν, which seems to be compounded of ωρα and ιμαω; and, if so, the literal signification would be “extraction of hours.”
It is next to be observed, that certain degrees are anæretic; though, in the prorogation made into signs preceding, the only degree which is strictly anæretic is that of the western horizon; and it becomes so because it obscures the lord of life; while other degrees, of stars meeting with or testifying to the prorogator, both take away from and add to the aggregate amount of the prorogation, which would otherwise continue until the descension or setting of the prorogator. Of these last-mentioned degrees, however, there are none properly anæretic; since they are not borne to the prorogatory place, but, on the contrary, that place is carried to their positions.[148] In this manner the benefics increase the prorogation, but the malefics diminish it; and Mercury assists the influence of either party with which he may be configurated. The amount of the increase or diminution is indicated by the degree, in which each star, so operating, is exactly situated; for the number of years will depend upon, and correspond with, the horary times[149] proper to each degree; and if the birth be by day, care must be taken to calculate the diurnal horary times; if by night, the nocturnal. These directions are to be understood as applicable to instances wherein the degrees in question may be in the ascendant; if farther advanced, a deduction proportionate to the distance is to be made, unless they should be on the occidental horizon, in which case there can be no remainder.
Therefore, whenever there may be found two or more conflicting configurations, auxiliary on the one hand, and hostile on the other, due observation must be made to ascertain which party surpasses the other, in power as well as in number. The pre-eminence in number will be, of course, obvious, from the greater number[154] on one side than on the other; but, for pre-eminence in power, it must be seen whether the stars, auxiliary or hostile as the case may be, are, on the one side, in places appropriate to themselves, while they are not so on the other; and especially whether those on the one side may be oriental, and those on the other occidental. It is also to be observed, in all cases, that not any one of such stars, whether hostile or auxiliary, is to be left out of the present calculation, on account of its casual position under the sunbeams.[155] This rule must be particularly attended to, because, even though the Moon be not prorogatory, the solar place itself becomes anæretic, if shackled by the simultaneous presence of a malefic, and not restored to freedom of operation by any benefic. [154] Of the stars and places brought into configuration. [155] Whalley’s translation of this passage is in direct contradiction to the sense: and even that of Allatius, as well as other Latin ones, are (if strictly correct) confused in their meaning.
The number of years, depending on the distances between the prorogatory and anæretic places, cannot be always gathered simply and at once from the ascensional times[156] of each respective degree; but only in cases when the ascendant itself, or some other specific degree or body, actually ascending in the oriental horizon, may possess the prorogation. For, if it be desired to calculate agreeably to nature, every process of calculation that can be adopted must be directed to the attainment of one object; that is to say, to ascertain after how many equatorial times[157] the place of the succeeding body, or degree, will arrive at the position preoccupied at the birth by the preceding body, or degree: and, as equatorial time transits equally both the horizon and the meridian, the places in question[158] must be considered, in respect of their proportionate distances from both these; each equatorial degree[159] being taken to signify one solar year. In conformity with the foregoing remarks, when it may happen that the prorogatory and preceding place may be actually on the oriental horizon, it will be proper to reckon, at once, the ascensional times which may intervene until the meeting of the degrees; because, after the same number of equatorial times, the anæreta will arrive at the prorogatory place; that is to say, at the oriental horizon. Should the prorogatory place be found on the meridian, the whole number of degrees by right ascension, in which the whole intercepted arc will transit the meridian, must then be taken. And if the prorogatory place be on the occidental horizon, the number of descensions, in which every degree of the distance will be carried down (or, in other words, the number of ascensions, in which their opposite degrees will ascend), is in that case to be reckoned.[160]
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