In reply to dinodinosaur:
E4s like Out For The Count and Under The Influence were put up by Bristol-based climbers Steve Monks and Nipper Harrison in the early 80s.
At that time, E4 was the highest grade in the Avon Gorge guidebook, reserved for the very hardest. Many routes brutally undergraded: Pinkginsane was given E4 by Nipper on the first ascent and is now E6; Magic Theatre, Already Gone and Don't Slip were all E3 in the 80s and are now given E5.
Pembroke routes put up by Bristol climbers were graded according to Bristol standards so current E4s often got E3 then. Some of their more popular routes have since been upgraded to bring them into line with the grades used by other Pembroke activists and guidebook writers. Not all though, some less popular climbs retain their original stern grades. It's worth checking the first ascentionist of the less frequently travelled routes.