Rig Veda
इन्द्रो॒ मधु॒ सम्भृ॑तमु॒स्रिया॑यां प॒द्वद्वि॑वेद श॒फव॒न्नमे॒ गोः । गुहा॑ हि॒तं गुह्यं॑ गू॒ळ्हम॒प्सु हस्ते॑ दधे॒ दक्षि॑णे॒ दक्षि॑णावान् ॥ इन्द्रो मधु सम्भृतमुस्रियायां पद्वद्विवेद शफवन्नमे गोः । गुहा हितं गुह्यं गूळ्हमप्सु हस्ते दधे दक्षिणे दक्षिणावान् ॥
Indra discovered the sweet milk secreted in the cow, and thereupon, brought forth (from their concealment) the herd (of cattle) having feet and having hoofs; munificent (in gifts), he held in his right hand that which had been hidden in the cavern, which was concealed in the waters.
english translation