Easy "Ghostbuster" Achievement...
	Various Steam Achievements...

In chapter four, when following the blood trail, you'll meet Norton. Before reaching the inn at the end of the chapter, you have to shoot him to scare him off ten times. You can wait around for him to spawn. You'll know he's close when the area gets foggy.

Complete the indicated task to unlock the achievement.

Achievement	How to unlock
Agent H.	Unknown.
Avid reader	Collect 10 notes as Nicolas.
Awakening the Beast	Unknown.
Bookworm	Collect all notes as Adam.
Boy with the matches	Collect 50 boxes of matches.
Breaking with the past	Unknown.
Citizen of Blackstone	Unknown.
Closed ward	Unknown.
Codebreaker	Unknown.
Cold Bastard	Unknown.
Eagle Eye	Find 10 hidden messages.
Erudite	Collect all notes as Nicolas.
Full tank	Collect 50 bottles of kerosene.
Ghostbuster	Unknown.
Gonzo journalist	Unknown.
Housekeeping	Unknown.
Librarian	Collect 10 notes as Adam.
Long Arm of Justice	Unknown.
Moth	Light 30 candles.
Newsflash	Unknown.
No noise	Unknown.
No secrets	Find all hidden messages.
Sparrow	Unknown.
Spycraft	Unknown.
The End of Madness	Unknown.
The True Beast	Unknown.
Where it all begins	Complete Chapter 1.