Intercepted SIGNS
The link here shows "Jack's Chart" with the two "intercepted signs"
=click on=
of Aquarius and Leo. Aquarius is in the 1st House, which begins in
Capricorn and ends in Pisces ~ completely enveloping Aquarius.
Likewise, Leo in the 7th House, is wholly in-between where that
house begins in Cancer and ends in Virgo. Thus, "intercepted."
There are 3 different house systems commonly used:
House: One of the twelve mathematically derived sections (houses) of a horoscope, each of which represents a particular area of life. The size of a house and the zodiacal degree that appears on its cusp depend upon the house system used.
Equal House horoscope: One in which twelve equal houses are derived by taking successive arcs of 30° each, beginning with the Ascendant and completing the zodiac circle. An alternate method bases the house cusps on the Midheaven rather than the Ascendant.
Placidean houses: The house system devised by the Spanish monk, Placidus de Tito (seventeenth century). Placidus' system, still widely used today, is based on the trisection of nocturnal and diurnal semi-arcs. The time it takes from each degree of the ecliptic to rise from the lower meridian to the horizon (nocturnal semi-arc) and to rise from the horizon to the upper meridian (diurnal semi-arc) is adapted to space.
Koch, Dr. Walter: The German astrologer who developed the Koch or Birthplace system of houses.
Edited: "fixed" sources link
http://www.astrology-numerology.com/glossary.html