16
Introduction
effects—the entire picture seems awash with blues and greens.
The depth at which all wave—lengths of sunlight are nally
absorbed varies according to the nature of the sea water. Obviously
if mud and sand particles are being swirled around in the surface
waters the light will soon be reected and scattered just like ordinary
daylight in a mist or fog. Animals and plants as well as their decaying
remains can also exercise a considerable inuence on the depth to
which light penetrates the oceans. Generally speaking, sufcient
light for plants to carry out photosynthesis—the process by which
they use light to convert simple chemicals into food—penetrates the
top few hundred feet in clear ocean waters. ln more turbulent
conditions, this gure is reduced considerably to less than the top
50 feet. Even in the most favourable conditions, by the time the
r,ooo—feet mark is reached the only colour is the deepest of blues
grading imperceptibly into black. The only light in these regions is
that provided by the luminous organs of animals which live at such
depths.
Oeeanogmpky to oeeanology
The extent of the world’s watery mantle was gradually unfolded
by adventurous voyages of exploration in the fteenth and sixteenth
centuries, when Columbus, Magellan and other navigators roamed
the seas. The goals of the early explorers and their sponsors had
little to do with probing the secrets of the oceans; they were more
concerned with nding new trade routes and territories, and the
serious study of the oceans had to wait several hundred years until
the nineteenth century. The rst really ambitions deep—sea expedi—
tion came on December 21, 1872 when a small sailing ship with
auxiliary steam power left Portsmouth. The Challenger did not
return to Britain for three and a half years, by which time she had
travelled over 68,890 miles of ocean. This pioneer expedition
organized by Charles Wyville Thomson, professor of natural
philosophy at the University of Edinburgh, is generally considered
to mark the beginning of oceanography, of what the eminent
Norwegian oceanographer H. U. Sverdrup dened as the ‘applica—
tion of all sciences to the study of the sea’.
The Royal Navy supplied both ship and crew under Captain
George S. Nares; Thomson selected the scientists and other
civilians needed for the expedition’s investigations. First they had
to transform Challenger from a warship boasting eighteen guns to a
Introduction
effects—the entire picture seems awash with blues and greens.
The depth at which all wave—lengths of sunlight are nally
absorbed varies according to the nature of the sea water. Obviously
if mud and sand particles are being swirled around in the surface
waters the light will soon be reected and scattered just like ordinary
daylight in a mist or fog. Animals and plants as well as their decaying
remains can also exercise a considerable inuence on the depth to
which light penetrates the oceans. Generally speaking, sufcient
light for plants to carry out photosynthesis—the process by which
they use light to convert simple chemicals into food—penetrates the
top few hundred feet in clear ocean waters. ln more turbulent
conditions, this gure is reduced considerably to less than the top
50 feet. Even in the most favourable conditions, by the time the
r,ooo—feet mark is reached the only colour is the deepest of blues
grading imperceptibly into black. The only light in these regions is
that provided by the luminous organs of animals which live at such
depths.
Oeeanogmpky to oeeanology
The extent of the world’s watery mantle was gradually unfolded
by adventurous voyages of exploration in the fteenth and sixteenth
centuries, when Columbus, Magellan and other navigators roamed
the seas. The goals of the early explorers and their sponsors had
little to do with probing the secrets of the oceans; they were more
concerned with nding new trade routes and territories, and the
serious study of the oceans had to wait several hundred years until
the nineteenth century. The rst really ambitions deep—sea expedi—
tion came on December 21, 1872 when a small sailing ship with
auxiliary steam power left Portsmouth. The Challenger did not
return to Britain for three and a half years, by which time she had
travelled over 68,890 miles of ocean. This pioneer expedition
organized by Charles Wyville Thomson, professor of natural
philosophy at the University of Edinburgh, is generally considered
to mark the beginning of oceanography, of what the eminent
Norwegian oceanographer H. U. Sverdrup dened as the ‘applica—
tion of all sciences to the study of the sea’.
The Royal Navy supplied both ship and crew under Captain
George S. Nares; Thomson selected the scientists and other
civilians needed for the expedition’s investigations. First they had
to transform Challenger from a warship boasting eighteen guns to a