Narada Purana (Jyotisha Selections) · by Vyasa
Chapter 2 · Signs, Planets, Birth
जातकम् १
होरे विषमभेर्केंदोः समभे शशिसूर्ययोः ।आदिपञ्चनवाधीशाद्रेष्काणेशाः प्रकीर्तिताः ॥ ३ ॥
In the full Narada Purana (Purva Bhaga) this is chapter 55, verse 3.
In the hora (half of a sign), an odd sign goes to the Sun and then the Moon. An even sign goes to the Moon and then the Sun. The drekkana (one-third part of a sign) lords are the sign's own lord. Then come the lords of its 5th and 9th signs.
Simple meaning: A sign's halves go to the Sun and Moon. Its thirds go to its own, 5th and 9th lords.
पंचेष्टाष्टाद्रिपंचांशा कुजार्कीज्यज्ञशुक्रगाः ।
Each sign has five parts of 5, 5, 8, 7 and 5 degrees. They go to Mars, Saturn, Jupiter, Mercury and Venus.
क्रियणतौलिककर्काद्या मेषादिषु नवांशकाः ।
Navamsha counting starts from Aries, Capricorn, Libra and Cancer. The twelfth parts are counted from the sign itself.
गोजाश्च कर्कयुग्मेन रात्र्याख्या पृष्ठकोदयाः ।
Taurus, Aries, Cancer and Gemini are night signs. The rest are day signs. Pisces rises both ways.