Johannes Brahms - Did Puck Grow a Beard??

In a book of various doctoral and other papers written by British musicologists, edited by one Bacharach, one of the papers dealt with Brahms, written during the great composer's life span.
One event recorded was as Brahms leaving a party, and at the door he bellowed "if there is anyone here whom I have not insulted, please forgive me!"
The other event was centered around an overstuffed chair which had been "tampered with" by Brahms, and was located in his apartment. Brahms would offer his visitor, often a lady, this comfortable chair, and upon sitting down, the victim's feet would immediately be pointed toward the ceiling.
Apocryphal or not, these two events were cast upon paper during the composer's reign, and are in print. if one should like to search for them.