Courtesy of NOAA Digital Library

Not only did the research vessel CHALLENGER (studied earlier) provide the first extensive view of the oceans, but the Voyage of the Fram (1893- 1896) under the direction of Fridtjof Nansen established the fact that the Arctic Ocean was not a shallow sea, but a deep ocean. This wooden ship was constructed in such a way as to be frozen into the ice of the Arctic Ocean. In fact, you might say that this was the first oceanographic ship constructed for a specialized mission. Part of that mission was to drift across the North Pole. And although this aspect of its mission to float across the North Pole failed, it succeeded by vindicating Nansen's theory of a westward current across the Artic Ocean.

In 1952 C.O.D. Iselin, and J.D. Issacs, designers of oceanographic instruments, stated, " the ship is the arm of the oceanographer, the cable his sinew, and the instruments his fingers grouping into the unknown". This statement couldn't be more true today with the change in techniques and instrumentation.

We once measured the depth of the ocean bottom with a sounding line, then sounding waves, and today we can map the ocean bottom from a satellite's orbit. And the amazing aspect of using satelllites, is, that the mapping is accomplished by measuring the the sea height.

Along with the research ship, the submersible , or deep submergence research vessel, is the other workhorse of the oceanongrapher. Prior to 1961, no deep submersible had been built, unless one takes into account William Beebe's Bathysphere. The Thresher accident in 1963 and the U.S. Navy's growing interest in deep submergence activities spawned the development of these vehicles. One of the first deep submergence vessel to be constructed was Alvin. It was constructed in 1965 and is operated by the Office of Naval Research at the Woods Hole Oceanographic Institution. One of the greatest advantages of a submersible is its ability to provide direct observations of a phenomena and to operate instruments independently of wave action.

But with the advantages, there are also disavantages with deep submersibles. These include:

• Dependence upon surface ships to transport them to the dive sites.
• Their size makes for uncomfortable quarters for carrying out their mission.
• Must be launched and recovered in mild seas.