'Modern air' inside those 3 old coffins Lab studies detect man-made CFCs

January 12, 1993|By Frank D. Roylance | Frank D. Roylance,Staff Writer

There was no 300-year-old air trapped inside St. Mary's City's lead coffins, after all.

"I think it's modern air," said Dr. Joel Levine, the atmospheric scientist who led the air analysis by scientists at NASA's Langley Research Center, in Hampton, Va.

The coffins, buried beneath the floor of the 17th-century Great Brick Chapel, contained the remains of two adults and a baby thought have been members of Maryland's founding Calvert family. Scientists had also hoped to find pristine, Colonial-era air trapped inside.

"We have done extensive analyses in the laboratory of the samples we took, and at this point we have unambiguously detected chlorofluorocarbons," Dr. Levine said yesterday.

Chlorofluorocarbons, or CFCs, are modern, man-made compounds. Because they have dispersed throughout the environment since they were first manufactured in the 1940s, they were chosen by the NASA researchers as the chemical "red flag" that would signal the presence of modern air inside the coffins.

The search for a sample of preindustrial air was a major component of the lead coffins project when digging began Oct. 1.

Scientists had hoped to compare the chemistry of "old" air from the coffins with that of modern air in order to measure how much the atmosphere has been altered by industrial pollution and the burning of fossil fuels since the Industrial Revolution.

"That's the way it goes," said Dr. Henry Miller, chief archaeologist at Historic St. Mary's City. In any event, "we got a good [air sampling] system and it worked, and we can use it elsewhere, perhaps in England. We had to try."

Other studies resulting from the lead coffins project are continuing in laboratories from Boston to Williamsburg, Va., he said. Scientists involved in the project will gather to discuss their preliminary results later this year, perhaps in May or June.

Scientists' hopes of finding preserved preindustrial air in the coffins were always rated as slim. They rose sharply Oct. 23, however, when the largest of the three coffins held a partial vacuum briefly and appeared to be sealed as several liters of air were extracted from its interior.

That seal now appears to have been transitory. The other two coffins had visible holes.

While disappointed by the results, Dr. Levine said he was pleased with the technology developed to extract the sample.

"We have every confidence that it worked," he said. "If the possibility lends itself again, we will have some technology to apply to it."

"The second positive thing is that, because of all the media interest, I think a lot of people became very aware of global environmental issues," he said.

The search for preindustrial air will continue, he said, but no specific project has been planned.

In the meantime, Dr. Miller said, study of the three coffins and their contents continues.

The human bones have been sent for study at the Smithsonian Institution in Washington.

Hair, blood and tissue fragments were sent to the Armed Forces Institute of Pathology in Washington, where scientists have begun the search for genetic evidence -- DNA -- that might reveal any family relationships among the individuals whose remains were found in the coffins.

The wood interior coffins are undergoing six to 12 months of preservation work at St. Mary's City. Cloth fragments are being prepared for conservation at the state's archaeology lab in Crownsville.

The many insect remains found in the coffins are to be examined in Maryland by Dr. Theodore Suman, an entomologist at Anne Arundel Community College, and by experts at the Armed Forces Institute of Pathology for clues to the 17th-century environment and the season of each burial.

Pennsylvania State University scientists have offered to conduct neutron activation analyses of the lead. That data could pinpoint the source of the lead used in the coffins -- perhaps England or Wales.

Pollen samples are being analyzed at a National Park Service lab in Boston. The lead coffins themselves will be sent to the College of William and Mary in Williamsburg, Va., for preservation work.

Eventually, the human remains will be reburied where they were found. The state hopes to rebuild the Great Brick Chapel and properly mark the graves.

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