Sahih Bukhari
Good Manners and Form (Al-Adab)
Volume: 008 / Book Number: 073 / Hadith Number: 182
Narrated Anas bin Malik:
Allah's Apostle was on a journey and he had a black slave called Anjasha, and he was driving the camels (very fast, and there were women riding on those camels). Allah's Apostle said, "Waihaka (May Allah be merciful to you), O Anjasha! Drive slowly (the camels) with the glass vessels (women)!"