The Upanishads, Part 2 (SBE15)
Chapters
Brihadaranyaka-Upanishad: First Adhyaya: First Brahmana

^74:5 Two vessels, to hold the sacrificial libations, are placed at the Asvamedha before and behind the horse, the former made of gold, the latter made of silver. They are called Mahiman in the technical language of the ceremonial. The place in which these vessels are set, is called their yoni. Cf. Vagas. Samhita XXIII, 2.