Amazon.com (ISBN 006018891X, Hardcover)

"I am making haste to pass on the contents to 25. 13. 8. 9. 38. . . . who has ordered me to open communications with you." So reads a French dispatch captured by the British in the Peninsular Campaign against Napoleon's armies, causing the Duke of Wellington to comment, "The devil is in the French for numbers"--and occasioning Mark Urban's intriguing study of code making and code breaking.

The early 19th-century British army was hidebound by tradition, writes Urban; elegant and well-placed gentlemen gained command, while more deserving but lower-born men languished in the ranks. Against that army, in Spain and Portugal, stood Napoleon's forces, "the mightiest armament since the legions of ancient Rome." Thanks to one common-born officer, George Scovell, a linguistic genius and adept solver of puzzles, Wellington's forces avoided disaster by learning of the superior enemy's plans--though, after the war, Wellington dismissed Scovell's contributions and took credit for himself and his favorite staff officers. A fine chapter in the history of intelligence and cryptography, Urban's book provides a fascinating aside to the well-documented Napoleonic Wars. --Gregory McNamee