"We dropped carbon black suspended in liquid, over a track a mile long and produced a solid line of clouds one mile long," Dr. Florence Van Straten told a reporter.
"When we dropped 1 1/2-pound dry packages of carbon black, we produced single clouds with each drop."
The navy team seeded seven clouds with carbon, and dissipated each of them in from 21/2 to 20 minutes. "Each cloud turned gray and then rapidly disappeared," Dr. Van Straten said.
"Aside from the cost of the airplanes, we spent less than $5 on the experiments in Georgia." 
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