Dennis Martin 1969 Case Solved?

"Some visitors come for the wildlife, while others are drawn to the grist mills, barns, log houses and churches scattered along the 11-mile loop road.


Last week, Keith Langdon came for the sinkholes.


A retired biologist for the Smokies, Langdon was in the right place ? the cove's limestone bedrock makes it a hot spot for sinkholes and caves ? and to aid his search, he had a special map, one that depicted Cades Cove as lunar landscape.


Maps of the Smokies have come a long way since the mid-1800s when Swiss geographer Arnold Guyot measured the high peaks along the Tennessee-North Carolina divide by calculating the altitude with a barometer.
Langdon's map is based on a remote sensing technology called Light Detection and Ranging that uses laser pulses transmitted from an airplane and reflected off the ground to create highly detailed, three-dimensional images of the terrain.


To further enhance the map's realism, a computer-generated effect called "hill shading" casts shadows upon the sinkholes and hills, as if light is illuminating the landscape from the northwest.


Accompanying Langdon that day in Cades Cove was Tom Colson, the park's geographic information systems specialist, and Chris Rehak, a GIS intern for the park.


The map indicated a depression in the ground not far from the loop road. After a 20-minute walk, they located a tear-drop-shaped sinkhole in the woods. At the downslope end of the sink beneath the fallen leaves was a small hole in the ground that indicated a cave."