Decker found ample opportunities to make himself useful. A few hours into their work, as he was helping to place a large microscope back into its crate, two scientists, Ray Rogers and John Heller, were standing by an adjacent crate, discussing their experiment. Their work would involve the only true sampling from the Shroud, which would be done by placing strips of tape onto the ancient cloth. When the tape was pulled up, small fibers would be removed with it. Decker listened as Ray Rogers explained the plan to Heller.

⁵ Don Devan's comments paraphrased. For actual words as recorded by Dr. John H. Heller, see ibid., p. 82.

"To obtain samples for the chemical investigation, including your blood work, we'll be using a special Mylar tape with a chemically inert adhesive developed by the 3M Corporation. We'll apply the tape to the Shroud using a known amount of force… "⁶

"How will you do that?" Heller asked.

"Well," Rogers said, as he reached into one of the packing crates, "our friends at Los Alamos have designed an ingenious little device that measures applied pressure." Rogers unpacked the device and demonstrated it to Heller.

"Nice, but how will you know how much pressure to apply?" Heller asked.

"Well," said Rogers, "that's why we're here."

Decker followed the two men as they squeezed in around the crowded table. After making the necessary preparations Rogers made some 'guesstimates.' "We know the Shroud is at least six hundred years old," he said, "so it's probably quite a bit more fragile than this. I'd guess to be safe we should probably use, oh, about ten percent of the pressure we're using here." The decision, Decker realized, was a SWAG (a scientific wild ass guess) but he wasn't about to utter a discouraging word at this point. "Next, I'll remove the tape from the Shroud," Rogers continued, "and mount each piece on a slide. Each slide will be numbered and photographed, and then it will be sealed in a plastic case to ensure it remains uncontaminated."