Spyglass

"Fitz, give me your glass." ―Jack Sparrow to Fitzwilliam P. Dalton III Spyglass is a small hand-held telescope used to spot land or an incoming ship in the distance.

Usage
Sneakin + left-click with a spyglass in hand will identify the block and its coordinates at the crosshair. It is useful on the sea where it can be used to identify flags of ships through darkness and fog.