Abu Dawud Book 002, Hadith Number 0399.

Chapter : Not known.

Narated By Jabir ibn Abdullah : I would offer my noon prayer with the Apostle of Allah (pbuh) and took a handful of gravels so that they might become cold in my hand and I placed them (before me) so that I may put my forehead on them at the time when I would prostrate. I did this due to the intensity of heat.