The Upanishads, Part 2 (SBE15), by Max Müller, , at sacred-texts.com
1. Let him meditate on speech as a cow. Her four udders are the words Svâhâ, Vashat, Hanta, and Svadhâ 1. The gods live on two of her udders, the Svâhâ and the Vashat, men on the Hanta, the fathers on the Svadhâ. The bull of that cow is breath (prâna), the calf the mind.
193:1 There are two udders, the Svâhâ and Vashat, on which the gods feed, i.e. words with which oblations are given to the gods. With Hanta they are given to men, with Svadhâ to the fathers.