I came to the Prophet (ﷺ) while he was inside a red leather tent, and I saw Bilal taking the remaining
water of the ablution of the Prophet, and the people were taking of that water and rubbing it on their
faces; and whoever could not get anything of it, would share the moisture of the hand of his
companion (and then rub it on his face).
Sahih al-Bukhari Book 77, Hadith 76