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Encyclopedia of Astrology (Nicholas deVore)

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Ides. A day in the Roman calendar and seven days before it. It appears that the term applied to the day on which the Sun passed the points of the Equinoxes and the Tropics, and that the seven days constituted the orbs preceding the Sun's crossing of the cusps of the four cardinal signs or angular houses. Shakespeare refers to the baleful influence of "The Ides of March" - evidently the last seven degrees of Pisces, or of the Twelfth House.

Illumination, Period of. That portion of the Moon's orbit, of the duration of approximately 26d 18h, during which it is visible, supplying light after sunset and before sunrise. Obviously it supplies light only to the hemisphere which is turned in its direction; but since the Earth's rotation constantly shifts this hemisphere, the whole of the Earth's surface is illuminated for some portion of every night during this period.

Immersion. Applied to the Sun or Moon as it enters into an eclipse, or to the beginning of an occultation (q.v.).

Impeded; Impedited. Said of a Luminary or planet when badly aspected, especially by the malefics. Also said of the Moon when passing to a conjunction, square or opposition to the Sun, Mars, or Saturn. The Moon when impedited by the Sun at birth was anciently said to produce a blemish in or near the eye.

Imperfect Signs, Broken Signs. Leo, Scorpio and Pisces. v. Signs.

Imum Coeli. The lowest heaven, the North Angle or cusp of the fourth house. v. Midheaven; Celestial Sphere.

Inclination. (1) Astrologically, the motion of a body toward a position in the horoscope other than the one it held at birth. (2) Astronomically, the angle at which the orbit of a planet crosses another orbit, particularly the ecliptic. A point in an orbit is reduced to the ecliptic by subtracting from the vector, the cosine of the declination.

The inclination of the Moon's orbit to the ecliptic varies from 4°59' to 5°18'.

The Earth's orbit is, of course, the Ecliptic, hence the Sun can have no latitude. That it has declination is due to the fact that the ecliptic makes an angle with the celestial equator of approx. 23°5' - which is described, not as inclination but as the obliquity of the ecliptic. For the inclination of the planets v. Nodes of the Planets.

Inconjunct. Dissociate. A planet is inconjunct when it forms no aspect and is not in parallel of declination or mutual disposition to another planet. Dissociate was formerly applied by some authorities to the 150° or Quincunx aspect, which they deemed inconsequential; but is now applied to any two Signs or Houses which have no familiarity with each other - meaning those which bear a twelfth, second, sixth and eighth House relationship, as Taurus, with Aries, Gemini, Libra and Sagittarius.

Increasing in Light. Usually said of the Moon, but equally applicable to any planet which, on leaving a conjunction with the Sun, increases in light, as viewed from the Earth; and as it recedes from the opposition, decreases in light.

Increasing in Motion. A planet increases its motion by acceleration from day to day as it approaches perihelion. When it is approaching its apogee, the Moon may advance 12° one day and as much as 13° the next. As its mean motion is 13°10' per day, any excess above this indicates that the Moon is "swift in motion." The condition is regarded as fortunate. Older authorities term it increasing in number.

Individual Houses. v. Houses.

Inferior Planets. The minor planets, those whose orbits are within that of the Earth: viz.: Mercury and Venus. v. Planets.

Infortunes. Mars and Saturn. v. Planets, Malefic.

Ingress. Said of the entry of any orbital body into a Sign, or a quadrant. The Sun makes an ingress into the Cardinal Signs at the equinoxes and solstices. The planets also have their ingresses into the various Signs, which result in certain alterations of their influence.

Initiating Signs. The first Sign of each season of the year; the Cardinal Signs - Aries, Cancer, Libra, and Capricorn, characterized by a constant state of mobilization for action.

Initiative Type. Referring to a quality liberally possessed by those born when the Sun was in a leading Sign: Aries, Cancer, Libra, or Capricorn. v. Sign.

Injunct. An abbreviated form of inconjunct (q.v.).

Inspirational Natures. Referring to the quality of sensory receptivity and reaction that characterizes those born with the Sun in Aries, Leo and Sagittarius - respectively, the initiative, executive and deductive types of the Inspirational group. It would appear that their chief motivation derives from a super-consciousness of the Ego.

Intellectual Natures. Referring to a quality of sensory receptivity through the mind that characterizes those born with the Sun in Libra, Aquarius and Gemini - respectively, the initiative, executive and deductive types of the Intellectual group. To classify this group as Intellectuals, does not imply that other groups are possessed of inferior intellects.

Interlunar. Of or pertaining to the brief period of time that separates the old and the new Moon. The period of the Moon's invisibility during a lunation, the solar period less 26 d., 18 h., or approximately two days.

Intercepted. Said of a Sign wholly contained within a House; or more precisely, of a House which is intercepted by a Sign which does not appear upon either of its cusps. v. House.

Interpolation. The process of computing intermediate values in a series of numbers. In astrology it is applied (1) to computing a planet's position for a given moment between two known posi- tions, such as the noon or midnight position prior to and subsequent to the desired moment, as taken from an Ephemeris for that year; and (2) to compute the house cusps for an intermediate latitude between two sets of tables computed for latitudes on either side of that for which the interpolation is required. In making the calculations necessary for an interpolation, use is frequently made of Tables of Diurnal Proportional Logarithms. v. Logarithms.

Interpretation. Applied astrologically to an individual judgment as to the significance of a configuration of birth planets, or of transiting or progressed aspects to a birth configuration.

Invariable Plane. The Solar System possesses two fixed planes: that of the Solar Equator; and the Invariable plane - a central plane of the Solar System discovered by Laplace, which, passing through its center of gravity at a mean inclination of about 1°35' to the Ecliptic, is independent of the mutual perturbations of the planets. The inclination of the orbits of Venus and Mercury to the Solar Equator, slightly more than 3 degrees, is less than that of the other planets. Since these are the two closest planets to the Sun, the Solar Equator can be considered as their reference plane. The Earth's inclination to this plane, of slightly more than 7", is exceeded only by that of Pluto. The Ecliptic, the Earth's plane of revolution around the Sun, intersects the Solar Equator in the middle of Gemini and Sagittarius, at which points the Earth has no heliographic Latitude North or South. However, the values of these inclinations and the longitudes of the planetary Nodes along this plane are all variable due to motions of the orbits themselves with respect to the other great reference plane of the Solar System: the Invariable Plane - so-called because its position remains unaltered by any forces within the system. In this plane the combined angular momenta of all the planets is a maximum. There are two classes of disturbances in the normal undisturbed elliptical motion of the planets in their orbits in space: periodic perturbations and secular perturbations. Periodic perturbations are deviations due to the gravitational pulls of the planets on each other. However, after the planets have revolved a considerable number of times, and thus have been in all possible relations to each other, these periodic perturbations cancel each other. A famous example is the long period inequality in the motions of Jupiter and Saturn, which shifts their positions by a degree or so - one forward and the other backward - in a period of about 918 years. Actually their recurrence cycle in the fixed Zodiac - 46 conjunctions distributed nearly evenly in all 12 Signs of that Zodiac - is about 913½ years, but the inequality lengthens this to 918 years. Therefore the periodic perturbations are determined by the second order recurrence cycles of the planets in the fixed Zodiac. However, at the end of such a cycle of fluctuation the distorting effects have not been completely cancelled out, and small remaining residues show up in what are termed the elements of the planets' orbits. As a result of this residue, the nodical line at which the orbit plane of each planet intersects the invariable plane, is displaced backward, in a precessional motion of the whole orbit plane. In addition, the inclination of the orbit plane to the invariable plane is slightly decreased or increased. A third effect is a shift in the position of the major axis - longest axis of the orbital ellipse. This shift may be either forward or backward, but it is more likely to be forward for all of the planets except Venus. Finally the shortest axis of the orbital ellipse - the minor axis which crosses the major axis at the center of the ellipse - increases or decreases its length; i.e, the eccentricity of the ellipse becomes greater or less.

Two great masters of celestial mechanics, Lagrange and Laplace, demonstrated that while there are periodic fluctuations in the lengths of the major axes there are no secular perturbations - long-term oscillations. Since the duration of a planet's revolution around the Sun depends on the major axis alone, this means that except for minor short-term fluctuations the periods of the planets are constant. They further demonstrated that the inclinations and eccentricities oscillate within narrow limits which are never exceeded, thus preserving the stability of the Solar System. Finally they showed that the orbit planes precess backward along the invariable plane, while most of the major axes revolve forward - spending briefer periods in actual retrograde motion. Only the major axis of Venus spends more time revolving backward than forward. Thus the Solar System, through an intricate process of mutual adjustment, maintains its basic configurations of orbits, and its stability. As one planet decreases its eccentricity and inclination, one or more orbits must at the same time be increasing their eccentricities and inclinations: whereby the total amount of eccentricity and of inclination to the invariable plane remains constant! This has been termed the Magna Charta of the Solar System. The late Ernest W. Brown showed that the effects of resonance could not have been great enough within the past hundred million years to have destroyed this stability; nor would it be in the next hundred million years.

Jupiter, the most massive of all the planets, has an orbital inclination to the Invariable Plane which never exceeds 0°28', nor ever less than 0°14'. Its current value is about 0°21'. Furthermore, the Nodes of the Jupiter and Saturn orbits on this plane are never separated from each other by much less than 180°; hence these two planets largely determine the position of the Invariable plane - especially Jupiter. According to Stockwell, the mean period of their common precession is 49,972 years. Similarly the perihelion ends of the major axes of the orbits of Jupiter and Uranus never get much less than 180 from each other. The common mean period for a revolution of their major axes (line of apsides) is 348,700 years. Thus Jupiter is the "flywheel" which balance the Solar System, a perfect symbol of justice and law.

The Earth's orbit - the ecliptic - can never have an inclination to the Invariable plane in excess of 3°6'. The value on January 1, 1850 was 1°35'19.376" - the figures are taken from Stockwell's "Secular Variations of the Eight Principal Planets," in the "Smithsonian Annual Contributions to Knowledge," Volume 18, 1872. According to him the maximum eccentricity of the Earth's orbit is .0693888; the current value .0159. The period of the orbital precession of the Ecliptic on the Invariable Plane is indeterminate, since the minimum inclination of the Ecliptic to that plane is 0°0'0". Similarly, the minimum Eccentricity is also 0, hence the mean period of motion of the line of Apsides is also indeterminate.

LeVerrier, the discoverer of Neptune, and Stockwell, calculated the position of Earth's perihelion, one end of the line of apsides, over a period in excess of 4,000,000 Years. By counting the number of times the line of Apsides revolved within that period, one gains a good estimate of its period in the present Mahayuga. This Mahayuga of the Hindus is a period of approximately 4,320,000 years, in which they say all of the planets recur at nearly the same position. The astronomer Stuart showed that this is correct and that the period is 4,319,936.8663 years: at the end of which Mercury, Venus, Earth, Mars, Jupiter and Saturn return to a position in the Fixed Zodiac about 20° behind where they started. He found this also applied to the "new" planets, Uranus and Neptune; and that an increase in the period of Pluto of only one part in 100,000, or 0.001 per cent, will also bring it into recurrence. It would appear that in the present Mahayuga the mean period of revolution of the Earth's apsides is about 115,000 years from LeVerrier's figures, and about 110,000 from Stockwell's somewhat more accurate figures: and the average period of revolution of the major axis of the Earth's orbit must have a mean value of approximately the same order of magnitude: i.e., 110,000 to 115,000 years.

In the present cycle both of these periods are near minimums, since the eccentricity and inclination of the Earth's orbit are decreasing to minimum values. In the current cosmic Era the length of the Planetary Precession and rotation of the Line of Apsides will be from 72,000 to 75,000 years. The minimum inclination will be reached in about 20,000 years and the minimum eccentricity about 26,000 A.D., one cycle of general Precession after Christ. The last Stationary position of the Perihelion-Stationary-Direct after several thousands of years of retrogressive motion - was about 26,000 years before Christ: again one cycle of the general Precession.

The relationships of these cosmic cycles to the time of the Christ is indeed remarkable, and tends to confirm the belief that a new cycle of general Precession then commenced. Furthermore at that epoch the Nodical line of Ecliptic and Invariable Plane was at right angles to the Nodical line of Ecliptic and Equator - the Equinox - thus making a Cross! The position of the Nodical line of the Planetary precession in the Moving Zodiac was 16°14'6.00" Cancer-Capricorn on January 1, 1850. The present position of the Perihelion end of the Line of Apsides - where the Earth is nearest the Sun - is about 11° Capricorn, i.e., the position of the Sun on or shortly after January 1 of every year (deviation due to Calendar variation or Leap Year effect). Thus it appears that we commence our year at what after all is astronomically the most logical time.

The minimum eccentricity of the Earth's orbit, at about 29,900 A.D., will be the smallest minimum since the greatest maximum, about 850,000 B.C., showing a great cycle, governing all planetary eccentricities in the Solar System, of a duration of approximately 1,750,000 years. According to Madame Blavatsky's "Secret Doctrine" it was around 850,000 B.C. that the first and most serious cataclysm destroyed most of the continent of Atlantis, at the start of what she terms the Fifth Root Race. As a cataclysm by Water, this suggests that the next cataclysm may be by Fire, and will occur about 25,900 A.D., at the start of the Sixth Root Race. Since she maintains that each Root Race has 7 Sub-races and each of these in turn 7 Family Races, there should be 49 Family Races in a Root Race or Lifewave. She also states that the period of a Family Race was that of the general Precession, a little under 26,000 years - although the Root Races overlap, in that a new one commences before an older one has run its course. It is easy to show that the Precession which ended with Christ was the end of the Fifth Family Race of the Fifth Subrace of the Fifth Root Race: making 33 Family Races or Precessions since 850,000 B.C. Therefore the present Sixth Family Race, of the present cycle of Precession, may be considered as a bridging cycle out of which both the Sixth Sub-Race and the Sixth Root Race will in the next cataclysm approach their start around 25,900 A.D.

The foregoing is not put forward dogmatically, but as an interesting explanation of the significance of these long cosmic cycles. The implication is that the present cycle of Precession is a bridging cycle between two great Lifewaves (Root Races), and thus has extraordinary importance; that it commenced with Christ and the cosmic Cross formed by the Equinoxes and the Line of the Planetary Nodes; and that the significance of the Crucifixion is essentially cosmic, and the Mission of the Christ one of initiating the great Precessional cycle of Transition from the Fifth to the Sixth Lifewave. It is a notable fact that on April 1, 25 A.D. (Julian Calendar), when Jesus was 30 years of age and at the start of his mission, according to a consensus of historical researches, there was a Great Cardinal Cross, wherein Uranus in Cancer at its Node on the Invariable Plane opposing Neptune in Capricorn at its Node on the Ecliptic, was in cross relationship to Saturn in Aries at its Node on the Equator opposing Jupiter in Libra - all the Nodes on the three basic planes which at that time were forming the cosmic cross. In addition there was a Full Moon in Libra with the Sun in Aries, Mars in Aries also in the Cross, and at its Node on the Ecliptic. Pluto was in early Sagittarius; and Mercury and Venus were retrograde in the last decan of Pisces - the Sign of Christianity and of the traditionally first of the 12 Ages into which the Precessional cycle is customarily divided. Thus through the crossing of orbit planes, the Nodes, this Planetary Cross shows a remarkable relationship to the Cosmic Cross made at that time by the Equator, Ecliptic and Invariable planes.

This full discussion is warranted on the basis that this date marks the blending of all the chief cycles which affect the Earth, and the significance of the cosmically-indicated Crucifixion of Christ, which could never before have occurred in the two-billion-year history of the Earth. A third Cross is found to be involved, if one considers the four consecutive Solar eclipse paths which passed over Jerusalem and Bethlehem, both before and after the life of Jesus. The total Eclipse of July 4, 336 B.C. at 6.3° Cancer; the total Eclipse of April 2, 303 B.C. at 7.5° Aries; the annular Eclipse of January 5, 29 B.C. at 12.6° Capricorn; and the annular Eclipse of October 4, 590 A.D. at 13.2° Libra - all Julian dates. These form a Cross in their positions on the Ecliptic (Zodiac), the positions in near-agreement with the Zodiacal places of the four chief major planets on April 1, 25 A.D.: Uranus, at 10.1° Cancer; Neptune, at 13.8° Capricorn; Saturn, at 4.8° Aries; and Jupiter, at 15.4° Libra - all calculated from Schoch's Tables by Ralph Kraum. Thus the Planetary Cross activated the Eclipse Cross (zodiacal), and the drama of the ensuing Crucifixion was enacted in Jerusalem where the four eclipse-paths had crossed and were to cross (Geographical), while both in turn were the projection of the basic evolutionary Cosmic Cross of the three fundamental planes which signified the commencement of the most vital cycle of Precession (both planetary Precession and general Precession), within the period of two Lifeways (transition from one to the other) - which is about 100 general Precessions or 2,570,000 years: the period of a double Polar Inversion. - CHARLES A. JAYNE, Jr.

Inversion. When any Angle which represents an aspect is subtracted from 180°, that which remains is also an aspect, and either is an inversion of the other. Thus: the inversion of a sextile is a trine; of a semi-square, a sesquiquadrate; and so on.

Ishtar. v. Venus.

Isis and Osiris. Two hypothetical trans-Plutonic planets which have been the subject of much conjecture.

Issat. (Izzah, glory; from Arabic.) Applied ironically to one who has delusions of grandeur, or who suffers from an exaggerated appraisal of his prestige.

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