It was the "first general survey of the deep-sea collections, undertaken with a knowledge of the circumstances under which the specimens were procured. "-C. Wyville Thomson, Voyage of the Challenger, Atlantic I and II.

362 Observation stations were established and at each one:

• "The exact depth was determinedSediment samples were recovered frome each stationWater samples from various depths were taken for physical and chemical analysesFauna were sampled at many depths using dredge or trawl for the bottom and nets for the upper depthsTemperature curves were determined at different depthsAtmospheric and Meteorological conditions were carefully observed and notedRate and direction of surface current was determined
• Attempts were made at some stations to determine the direction and rate of movement of the water at different depths."
  -C. Wyville Thomson, Voyage of the Challenger, Atlantic I and II.