New research has thrown light on a side of the Revolutionary War which the gentleman officers of the 18th Century found highly distasteful – but absolutely necessary. Washington’s Spies concerns the so-called Culper Ring, which was run by the General himself in order to obtain information about the British command, then directing their war effort from headquarters in New York City. (Nathan Hale’s unfortunate end appears to have been a direct result of an early, amateur effort to fetch information on troop movements out of the City.) Like all good spy stories, this one has quite a cast of characters, from farmers and innkeepers to the privateering whaleboatmen who plied Long Island Sound, and who sometimes played both ends against the middle. Braving the breakdown of law and order and vengeance killings that are features of any civil war, one of the more unlikely members of the Culper Ring was a genteel Quaker from a Loyalist family. As the war dragged on, the Americans became more sophisticated, employing not only ciphers and dead drops, but the latest in technology: invisible ink. The book is well illustrated, including maps, portraits, and original documents. An interesting section on the ciphering methods then in use is included. A fine addition to any Revolutionary War library.