अथ प्रथमोऽध्यायः ।प्रथमं ब्राह्मणम् ।उषा वा अश्वस्य मेध्यस्य शिरः ।सूर्यश्चक्षुर्वातः प्राणो व्यात्तमग्निर्वैश्वानरः संवत्सर आत्माश्वस्य मेध्यस्य ।द्यौः पृष्ठमन्तरिक्षमुदरं पृथिवी पाजस्यं दिशः पार्श्वे अवान्तरदिशः पर्शव ऋतवोऽङ्गानि मासाश्चार्धमासाश्च पर्वाण्यहोरात्राणि प्रतिष्ठा नक्षत्राण्यस्थीनि नभो मांसानि ।ऊवध्यं सिकताः सिन्धवो गुदा यकृच्च क्लोमानश्च पर्वता ओषधयश्च वनस्पतयश्च लोमानि ।उद्यन् पूर्वार्धो निम्लोचञ्जघनार्धः ।यद्विजृम्भते तद्विद्योतते ।यद्विधूनुते तत्स्तनयति ।यन्मेहति तद्वर्षति ।अहर्वा अश्वं पुरस्तान्महिमान्वजायत ।तस्य पूर्वे समुद्रे योनिः ।रात्रिरेनं पश्चान्महिमान्वजायत ।तस्यापरे समुद्रे योनिर् ।एतौ वा अश्वं महिमानावभितः सम्बभूवतुः ।हयो भूत्वा देवानवहद्वाजी गन्धर्वानर्वासुरानश्वो मनुष्यान् ।समुद्र एवास्य बन्धुः समुद्रो योनिः ॥बृह.१,१.२ ॥
In plain words
The dawn is the head of the sacrificial horse; the sun is its eye, the wind its breath, the fire Vaiśvānara its open mouth, the year the body of the sacrificial horse. The sky is its back, the middle region its belly, the earth its underbelly; the quarters are its flanks, the intermediate quarters its ribs, the seasons its limbs, the months and half-months its joints, the days and nights its feet, the constellations its bones, the clouds its flesh. The sand is the food half-digested in its stomach, the rivers its entrails, the mountains its liver and lungs, the plants and trees its hair. The rising sun is its forepart, the setting sun its hindpart. When it yawns, that is lightning; when it shakes itself, that is thunder; when it makes water, that is rain. Its voice is speech. The day arose after the horse as the vessel called Mahiman that stands before it; its birthplace is in the eastern sea. The night arose after it as the vessel that stands behind it; its birthplace is in the western sea. These two vessels arose on either side of the horse. Becoming a steed it carried the gods, becoming a courser the Gandharvas, becoming a runner the demons, becoming a horse men. The sea is its kin, the sea its birthplace.