hospital in Zikhron Ya'akov. Yaffe's extensive knowledge of the importance of public health and the practical realities of Israel led him to build a widespread system of prevention. He trained crews of medics who could help settlers, and these crews spread throughout the land and improved the level of prevention and treatment in the population. In 1919, he moved from Zikhron Ya'akov to Haifa, where he worked as a doctor and published articles on medicine. His articles were published in newspapers outside the country, and he was invited to international medical conferences. Yaffe continued to work until his death in 1936. He was buried, according to his wishes, in Zikhron Ya'akov. Involvement with NILI Yaffe had minor but crucial involvement with NILI, the Jewish espionage network centered in Zichron Ya'akov which assisted the United Kingdom in its fight against the Ottoman Empire in Palestine between 1915 and 1917, during World War I. In Spies in Palestine, James Srodes quotes the diary of Yaffe as saying that Sarah Aaronsohn, after her botched suicide attempt, as she lay suffering & fearful that she would unintentionally reveal secrets to the Turks in her delirium (which she did not), pleaded with him, "For heaven's sake, put an end to my life. I beg you, kill me… I can't suffer any longer…" Instead, Yaffee administered a non-fatal dose of morphine, thus prolonging her life. She died several days later, on 9 October 1917. Fight against malaria Yaffe's first efforts to eradicate malaria focused on drying the swamps. He used many methods, including wide use of eucalyptus trees, on the principle that the large tree would draw a lot of water from the ground. Also, manual efforts were undertaken to dry the swamps. The residents of Hadera and foreign workers from Africa (who arrived after Yaffe requested help from Baron Rothschild) began the physically demanding labor of drying the swamps using a wide network of canals, connecting the swamps to the Hadera Stream. Another approach taken by Yaffe was research. Yaffe left for Europe and learned novel theories about malaria. Among these studies was one that suggested that mosquitoes from the genus Anopheles, which were prevalent in swamps, were carriers of the disease. He began to plead with farmers to hang canopies around the beds, nets around the windows, and to clean every pool of standing water. Likewise, Yaffe convinced Baron Rothschild to send men to