... they relate, that one day the prophet was taking a pleasure-walk under the guidance of Jabril, and came to a place where a great tumult was heard.  Jabril said: "This is the threshold of pleasure: enter into the house."  The prophet consented to go in, and there he saw sitting forty persons as naked as they came from their mother, and a band busy serving: but whatever service the prophet requested them to command him to do, they did not comply, until the moment to grind bang* arrived.  When they had ground it, they had no cloth through which they could strain and purify it; then the prophet, having taken his turban from his head, purified through it the juice of the bang, the color which remained on the turban; whence the garment of the Bini Hashem is green...
    *Bang is an inebriating, maddening draught, made of hemp-leaves, henbane, opium, or masloe. (The Dabistan, or, School of Manners, Fani, v.2, 1843)