Онлайн книга Monday Mourning

From 1950 to 1963, the values rose to about 85 percent above contemporary reference levels. In 1963, an international agreement halted atmospheric nuclear testing by most nations, and biospheric radiocarbon levels began settling into a new equilibrium.”

“Such folly.” LaManche wagged his head sadly.

“These permutations are known as the fossil fuel and atomic bomb effects.”

LaManche stole a glance at his watch.

“The bottom line is that artificial or ‘bomb’ Carbon 14 can be used to determine if someone died before or after the period of atmospheric nuclear testing.

“How is this test done?”

“There are actually two methods. With the standard radiometric technique, materials are analyzed by synthesizing the sample carbon to benzene, then measuring the Carbon 14 content in a scintillation spectrometer.”

“And the other method?”

“With the other method results are derived from reduction of the sample carbon to graphite. The graphite is then tested for Carbon 14 content in an accelerator mass spectrometer.

For several seconds LaManche said nothing. Then, “How much bone is required?”

“For conventional decay counting, two hundred fifty grams. For accelerator mass spectrometry, just a gram or even less.”

“AMS testing costs more?”

“Yes.”

“How much?”

I told him.

LaManche removed his glasses and squeezed the bridge of his nose with a thumb and forefinger.

“Is there no intermediate step to determine that such an expenditure is justified?”

“There’s one thing I could try. The technique isn’t terribly reliable, but it’s simple and might show if death occurred more or less than a hundred years ago.

LaManche started to speak.

“And free,” I added. “I can do it myself. But again, it will yield only a very rough indication of whether the bones are more or less than a century old.”

“Please.” LaManche repositioned his glasses and rose. “In the meantime I will discuss your proposal with Dr. Authier.”

Jean-François Authier, the chief coroner, considered all requests for exceptional expenditures.

Grabbing a lab coat from my office, I headed to the morgue. Morin and Ayers were already cutting Y incisions in room two. I requested a UV light, and waited while the tech got it. Then I hurried to the appropriate bay and pulled the left femora from skeletons 38426, 38427, and 38428.

In autopsy room four, I wrote the respective case numbers on the proximal and distal ends of the leg bones, and placed them on the autopsy table.