When do I unlock the Dickens-missions? I ran into Dickens for a brief moment in the beginning of the game. I have just finished Whitechapel and gotten the train. What does the Dickens marker look like on the map?

It looks like a C I believe (either that or a D), I think you have to do some of the Graham Bell stuff first before it's available, or maybe you need to finish the chapter.

@ares42: thanks!