Sayyiduna al-Mughirah (may Allah be pleased with him) said: We were with the Messenger of Allah (peace and blessings be upon him) on a journey. Along the way he (peace and blessings be upon him) stayed behind, and I too stayed behind with him, carrying a water vessel. He (peace and blessings be upon him) went aside to relieve himself, then came back to me. I poured water over the hands of the Prophet (peace and blessings be upon him), and he performed ablution; it was the time of the dawn prayer. When he (peace and blessings be upon him) had washed his face and wanted to wash his forearms, the sleeves of his cloak were too tight; he (peace and blessings be upon him) was wearing a Syrian cloak. He brought his hands out from beneath the cloak and washed his forearms, then completed his ablution and wiped over his leather socks.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الطهارة / 1297