Fibonacci Fisher - The Smithy Code Revealed
The answer is: "Jackie Fisher, who are you? Dreadnought."
John Fisher was First Sea Lord of the Royal Navy who (among other innovations) tried to get the British to go for fast, heavily gunned, but lightly armored battlecruisers, (bad idea; see HMS Hood) but was forced to realize that vision as a class of battleships, the first being the HMS Dreadnought, launched on February 10, 1906, 100 years before the DaVinci Code copyright infringement trial began.
The code was cracked by Dan Tench using the Fibonacci sequence, a number series described in The DaVinci Code. The Fibonacci sequence can also describe the Golden Mean, which also describes the curve of a nautilus shell.