CNN Death Row Stories March 23, 2014 01:39:00
>> like a clock. >> it sounds like a ticking clock or snapping your fingers. but it's not as loud as you may have expected it to be. so when you consider that and you consider how deep the water is, you consider the other competing noises within the ocean, when the waves are smacking around, it just really illustrates how difficult this job is. because you have to be within a two-mile radius to actually pick this up. obviously you don't usually hear it with the human ear. they have special equipment that's designed to detect that snapping sound that you just heard. >> renee, there's another pr...