Overseer Music Boxes

Overseer Music Boxes is an audiograph found in Dishonored, recorded by an unidentified Overseer.

Transcript
''We cannot doubt the effectiveness of Holger's Device, or the mathematical beauty of the music itself; we've seen it in action against the forbidden practices too many times to deny it. But the question no one wishes to ask is - is the incantation itself black magic? The boxes are priceless, but what's inside?''

Location
The audiograph can be found during the mission High Overseer Campbell, in the locked workshop in the Back Yard.

Die Spieluhren der Aufseher Pozytywki Rewidentów (audiogram) Carillon del Sacerdote 督军的音乐盒（录音） Шарманки_смотрителей