Fleishman said of Halvorsen: “The kid can never make the delivery in San Francisco alone. He’s too nervous and it is too risky. Polcuch had better go with him. We’ll rig up a story that Polcuch is Halvorsen’s shipmate and that they have been working together on the deal.” Fleishman told them it wasn’t practical to use the original eight sacks of heroin as a decoy in trapping the receiver in San Francisco. He agreed with officials in Washington that there was too much danger of the heroin being lost or stolen and being put back into the illicit market. Also there was the difficulty of obtaining legal clearances for transporting that amount of heroin across the continent. “We’ll have to ask the laboratory to find a substitute to put in those bags,” Fleishman said. “It will have to be something that looks, feels and tastes like heroin. We can blow this whole case if we’re not careful.” Fleishman knew the San Francisco receiver would become suspicious if Halvorsen didn’t show up soon. He picked up the telephone and asked his secretary to call the chief chemist in the Bureau’s Boston laboratory.... When Acting Chief Chemist Melvin Lerner put down the telephone after talking to Fleishman, he sent word to the laboratory that he wished to see Chemist Paul Leavitt. Lerner was a tall, brown-haired young man who had been with the Bureau for fourteen years. Lerner called for Paul Leavitt because this remarkable man had an uncanny sense of taste--and if anyone could find a material which tasted like heroin, it was he. Leavitt could identify accurately an enormous number of materials simply by tasting them, an odd sort of sensory skill which he had had since childhood. It had been a valuable asset in the laboratory, where he had spent almost forty years as a chemist. The problem was to find a light, white, powdery substance with the same bulk and weight as heroin and the same bitter taste. The taste was particularly important because it was characteristic of narcotics buyers to taste heroin before accepting it in any large amount. When Leavitt came into the office, Lerner outlined the problem that had been dumped into their laps and he gave him the details of the Halvorsen case. “How much time do I have?” Leavitt asked. Lerner said, “It’s a rush job, Paul. They want it in New York on the first plane tomorrow--in the same cotton bags which are out there in the vault. We’ll have to remove the heroin from the bags and refill them with a substitute material.” Leavitt knew that sacks filled with milk sugar or ordinary sugar would never fool a veteran trafficker in narcotics because the sugar would weigh ten times more than heroin. The substitute had to have the same bulk density as heroin.