You asked if we knew the book in question. I gave you a clue in my reply but you just didn't get it. "Grip" was the name of the raven in Barnaby Rudge!

Quite right. But it doesn't surprise me that you personally would have recognised it. However, there was as I recall enough to go on on that half page(riots,ravens) for others instead of wasting their time throwing irrelevant side-tracking stuff at me to have googled it successfully.