Periscope

The Wisconsin Maritime Museum has a working submarine's periscope.

Although this is an older model, additional information about slightly newer models of Naval periscopes can be found in Submarine Periscope Manual at The Fleet Type Submarine Online. Chapter 1 discusses some of the differences of the 92KA40T/1.4HA "Type II" periscope as compared to others described in the manual.

Chapter 1 also contains an instructive diagram showing how a periscope is mounted in a submarine.