Tethers. This underwater shot shows a little of our tether system under water. It is difficult to make out the “trapeze” that I told you about in the text, but you can see the three divers’ tethers converging on our down line, which is the thickest of the visible lines. Up above you can see the bottom of our dive zodiac and the considerable amount of texture that is typical of sea ice at this time of year. Photo by Joel Bellucci. C L O S E     W I N D O W