Abraham Woodhull Abraham Woodhull ( October 7 , 1750 – January 23 , 1826 ) was a member of the Culper Spy Ring during the American Revolution . After the Revolution , he served as a magistrate and a judge . It may be that James Fenimore Cooper ' s character Harry Birch was based upon his work as a spy . Background . Woodhull ' s father was a local judge who was linked to Patriot politics . Before 1776 , Woodhull may have briefly served with a militia company , but there is little to tie him to either side of the war until his spying . Historian Alexander Rose claimed Woodhull began working as a spy as part of the conditions of his early release from prison in Connecticut for engaging in trading . Spy ring . Woodhull developed a code to communicate with members of the patriot army that the British forces were unable to understand . This code was a series of letters and numbers that were put together and looked like nothing more than gibberish . Abraham Woodhull went by the name " Samuel Culper Sr . " so that the British did not discover who he really was , and harm him or his family . In some of his letters , Woodhull used a type of invisible ink ( gallic acid ) that needed to be doused in a certain type of chemical ( iron sulfate ) to be read . Woodhull also would deliver messages to him by burying the message in a box in a certain place , where he would know to look for it . This type of message delivery was known as a " dead drop " . Beginnings . Regardless of Woodhull ' s motives , he began spying in November 1778 . Woodhull ' s plan was to travel to Manhattan pretending to visit his married sister and her family at her boardinghouse . While in Manhattan , he would wander the city to collect information and then return to Setauket where he could the information to Major Benjamin Tallmadge writing with the pseudonym " Samuel Culper . " Predictably , this initial plan had problems . Woodhull ' s visits to his sister were too frequent to be understandable , especially given the danger . Additionally , he spent all of the time he was supposed to be visiting with his sister wandering the city without an obvious purpose , suggesting that there was another reason he traveled to New York . The British naturally became suspicious by the spring of 1779 . On June 5 , the Long Island - based Queens ' Rangers under the command of Colonel Simcoe were sent to the Woodhull family home to Abraham . Abraham was not at home at the time and avoided , but the Rangers attacked his father . Clearly , Woodhull ' s situation was too precarious to continue using the same plan . To escape the immediate danger of , Woodhull sought help from a friend who was powerful enough to personally with the " Gen ' l Aid , " a phrase that seems to refer to one of Major John André ' s many military titles . Woodhull recruited Robert Townsend , who lived at his sister ' s boardinghouse and was distantly related . Woodhull and Townsend also had some similarities in social status . Why Woodhull chose Townsend is not known , but Townsend sent his first report as " Samuel Culper , Junior " on June 20 , 1779 . Townsend was a much better choice as a spy since he had an obvious reason to be in New York . His mercantile background gave him a good reason to inquire about British troop movements and shipping . While Townsend ' s intelligence reports were a much better quality than Woodhull ' s , Woodhull and Tallmadge knew by August that they needed to do something different if they wanted decent intelligence . Improvements . On August 15 , 1779 , Woodhull wrote to Tallmadge , indicating that he planned to travel to New York shortly , and he had a plan involving the " assistance of a lady of my acquaintance " to " them all . " Many historians have interpreted this letter to mean that Woodhull recruited another agent who was a woman . Because people did not believe women in the 18th century were capable of independent activities or political allegiances , women were often capable spies . There is no further evidence to indicate that the Culper Ring had a female agent gathering intelligence for them , although there was a woman in Setauket who helped with the network logistics . Less than two months after Woodhull wrote this letter , the Culpers ' reports drastically improved , and they were feeding Tallmadge intelligence that could only come from the upper levels of British Headquarters . With the new structure of the ring , Woodhull no longer carried messages between New York and Setauket . He would simply retrieve Townsend ' s intelligence from a pre - arranged place on his property , where it was left by a courier . Woodhull ' s job was to simply collect the message , monitor for a signal from the whale boat ferry - man Caleb Brewster , and deliver the dispatches to Brewster . It is generally thought that Woodhull only needed to watch his neighbor Anna Strong ' s clothesline , where she would arrange her laundry to signal Brewster ' s presence and location . Woodhull only traveled to Manhattan when he felt there was a problem with Townsend he needed to discuss . The letters Woodhull wrote as cover letters or supplements to Townsend ' s dispatches are particularly valuable in some cases , particularly where Townsend ' s letters no longer survive . It was the urgent cover letters Woodhull wrote on July 20 , 1780 ( coinciding with the British discovery to the arrival of the French Fleet ) , that make historians think the Culpers discovered the British plans to attack the vulnerable fleet . Benedict Arnold discovery . When Major André was captured and the Benedict Arnold was discovered , Woodhull continued to report . Woodhull ' s dispatches often provided more information about the mindset and concerns of the ring , along with the dangers everyone faced . Also , it was Woodhull ' s dispatches that informed Tallmadge and historians of the capture of " friends " including " one who hath been ever serviceable to this correspondence " on October 26 , 1780 , during the period of Arnold ' s spyhunt . At the time Woodhull wrote that letter , Townsend was hiding at Woodhull ' s family ' s home , presumably because it would be easier to escape to Connecticut than in the Townsend family home , which was occupied by the British . In the aftermath of the Arnold plot , Townsend had an extreme emotional response , documented by Woodhull , and refused to continue spying until the following spring . However , Woodhull continued reporting , even though he had little information of any true value . Woodhull ' s reports were not of a particularly good quality , and after Andre ' s death , Townsend ' s few reports were also lacking . Aftermath . Following the war , Woodhull married his cousin Mary Smith in 1781 and had three children with her . He held a few minor political appointments , including Suffolk County , where he served from 1799 - 1810 . His wife died in 1806 , and in 1824 Woodhull married a woman named Lydia Terry . He died in Setauket in 1826 . He is a descendant of Richard Lawrence Woodhull , Esq . , a wealthy settler of Setauket and a relative of Major General Nathaniel Woodhull .