Qi ckTi ne?and a TI FF (Uhconpressed)deconpressor are needed to see this pi cture. Challenger Expedition (1872-1876) an outline of the main contours of the ocean basins, the discovery of the mid-Atlantic Ridge the then record 8,200 meters Challenger Deep in the Mariana Trench the discovery of prodigious life forms even at great depths in the oceanQui ckTi me?and a TI FF ( Uncompressed) decompressor are needed to see thi s pi cture. Challenger Expedition (1872-1876) an outline of the main contours of the ocean basins, the discovery of the mid-Atlantic Ridge the then record 8,200 meters Challenger Deep in the Mariana Trench the discovery of prodigious life forms even at great depths in the ocean