This is a set of instructions for clock tower maintenance, required to halt the gears in the TDS mission " Killing Time". There are a few of these scattered about the tower; one is at Father Debole's desk in the upper levels, and another in the foreman's office in the basement (both cylindrical scrolls). A third copy is pasted to the wall by the front door. Collecting any one of these will complete the objective, but only this last one can be read.
The plan includes instructions on gear maintenance and safety, as well as a map of the boiler room. Although the "New Map Acquired" heading appears when it is picked up, Garrett will already have this map if playing on the Xbox version.