One of the things I like to do in my CoC games is to use additional audio and visual props. CoC is a game that often utilizes props and I feel that adding to that can only help to reinforce the setting, particularly as CoC commonly uses historical settings.
So, with that in mind, I figured I'd toss them up here for the potential use of anyone else tackling this epic. My group plays in the room with the TV so I use PLEX to handle things as it lets me do audio, video and images.
It should go without saying that this is for GMs only and if you are intending to jump into this as a player you should probably bail out. Also, none of these are my images. They have all been collected online, some from public archive, some props created by other GMs, some just from random web searches.
IMAGE PROPS FOR LONDON