Narrated Anas bin Malik: That he heard Jabir bin `Abdullah saying, The roof of the Mosque was built over trunks of datepalms working as pillars. When the Prophet delivered a sermon, he used to stand by one of those trunks till the pulpit was made for him, and he used it instead. Then we heard the trunk sending a sound like of a pregnant she-camel till the Prophet came to it, and put his hand over it, then it became quiet.