The two men leading the CIOS chemical weapons team were an American officer named Lieutenant Colonel Philip R. Tarr and a British officer named Major Edmund Tilley. These men would soon become critical players in the Operation Paperclip story. Each was considered an expert in chemical warfare, but Major Tilley had a leg up on his American counterpart—at least in the field—in that he spoke fluent German. In addition to his role as a CIOS leader, Colonel Tarr was chief officer in the U.S. Army’s Intelligence Division of the U.S. Chemical Warfare Service, Europe. Unknown to Major Tilley at this time was that Colonel Tarr’s U.S. Army objective would soon supersede his loyalty to their work together as a CIOS team.
With American forces now on German soil, the fear that Hitler might unleash a devastating chemical weapons attack in a last-ditch attempt to make good on his wonder weapons promise was real, but Tarr and Tilley had very few leads as to where the chemical weapons might be stashed. German counterintelligence agents had done a brilliant job concealing the Reich’s nerve agent programs from foreign intelligence agencies during the war. Tabun had been given various code names, including Trilon 83, Substance 83, and Gelan 1. Even its raw materials were coded. Ethanol was “A4,” and sodium was “A-17,” making identification all but impossible. In 1942, a U.S. intelligence report entitled “New German Poison Gas” concluded that the possibility that Germany had new chemical weapons was “no longer seriously regarded.” Only in May of 1943, after capturing a German chemist in North Africa, did British agents learn of a colorless nerve agent of “astounding properties” being developed by IG Farben chemists in Berlin. The British interrogation officers found the German chemist’s information to be credible and wrote up a ten-page secret report for the Chemical Defense Experimental Establishment, which operated out of Porton Down. But the captured scientist knew only the substance’s code name, Trilon 83. Without further information, no action was taken by the British. Now, in March 1945, Tarr and Tilley were on the hunt for this mysterious Trilon 83 and anything else like it.
Leading the CIOS team into Germany, Tarr and Tilley inspected IG Farben factories at Ludwigshafen, Mannheim, and Elberfeld. At each location the officers noted with suspicion how remarkably little each town’s Farben scientists claimed to know. As far as intelligence collection was concerned, the scenario at each seized Farben factory was always strikingly similar: Where there should have been huge troves of company records, there were empty cabinets instead. Farben scientists who were taken into custody and questioned always said the same thing: IG Farben made chemical products for domestic use—detergent, paint, lacquer, and soap. And none of the scientists interviewed by CIOS officers claimed to have any idea where the bosses had gone.
In a CIOS memorandum, Tilley and Tarr expressed mounting frustration. One scientist after the next “lied vigorously about his activities,” the men wrote in their intelligence report, entitled “Interrogation of German Scientific Personnel.” Good, actionable intelligence remained out of reach. Then, as circumstance would have it, Alsos agents caught a huge break farther north in the city of Bonn.
Alsos had been trailing the Third Armored Division since it first rolled into Ludwigshafen on March 23. Several days later the soldiers liberated the city of Cologne and then set their sights on Bonn, some fifteen miles to the north. Scouting soldiers reported seeing men who might be professors burning caseloads of documents in Bonn University courtyards. What they couldn’t see was that inside university bathrooms, professors were also desperately flushing documents down the toilet, hoping to destroy evidence that might implicate them in war crimes. When the Allies finally secured the university, a Polish lab technician approached a British soldier to say that he had salvaged a large pile of documents that did not properly flush down a toilet bowl, as had apparently been intended.
These papers looked important, the lab technician said. And indeed they were. The man had turned over to British intelligence a classified list of the Reich’s top scientists. The officer handed the list over to Samuel Goudsmit of Operation Alsos. This group of documents would lead to what would become known as the Osenberg List.