Agni Purana (Jyotisha Selections) · by Vyasa
Chapter 3 · Name Letters and Chakras
युद्धजयार्णवः (चक्राणि)
भानोः पञ्चदशे ह्यृक्षे यदा चरति चन्द्रमाः ।तिथिच्छेदे तु संप्राप्ते सोमग्रासं विनिर्दिशेत् ॥ १९ ॥
In the full Agni Purana this is chapter 130, verse 19.
Say the Moon moves in the 15th nakshatra (star) from the Sun's. If a tithi (moon day) then ends, call it a Moon eclipse.
Simple meaning: When the Moon is in the 15th nakshatra from the Sun and a moon day ends, foretell a Moon eclipse.
प्रदक्षिणमकारादीन्स्वरान्पूर्वादितो लिखेत् ।
Write the vowels round a circle from the east. The months start from Chaitra. Moon days are listed next.
त्रयोदशी चतुर्दशी अष्टम्येका च सप्तमी ।
These moon days are listed. Twelve moon days are counted from the first to the thirteenth.
चैत्रचक्रे तु संस्पर्शाज्जयलाभादिकं विदुः ।
In this wheel, odd places bring good results like victory and gain. Even places bring bad results.