The fire in which oblations of ghee are offered at the Paurnamashya and at other sacrifices was a son of Brihaspati and that high-souled one is called Shanyu.
आहुतिष्वेव यस्याग्नेहविषाद्यं विधीयते। सोऽग्निद्र्हस्पतेः पुत्रः शंयुर्नाम महाव्रतः॥