The Mighty Deep

The Mighty Deep by Agnes Giberne

The Mighty Deep surveys the Ocean as a single world-wide body of water and traces humanity’s growing understanding of it. It begins with sea-loving ancestors and early mariners, especially the Phenicians, whose ventures beyond familiar coasts foreshadow later exploration. The narrative follows the widening of geographical knowledge through voyages associated with Bartholomew Diaz, Vasco da Gama, Christopher Columbus, and Magellan, while defending the value of patient inquiry into the natural world. The work explains the composition and saltness of sea-water, the circulation by which rivers carry water and minerals to the sea, and evaporation returns water to the land as rain. It describes the Ocean’s immense extent, its continental, transitional, and abysmal regions, its mountain-ridges, plateaux, and profound “Deeps.” Gravity, the attraction of land-masses, winds, the moon, and the sun govern the sea’s level, waves, tides, spring and neap tides, and destructive bores. Attention then turns to the hidden under-ocean. Soundings, dredges, thermometers, and the work of the Challenger expedition reveal a realm of darkness, cold, crushing pressure, slow currents, varied muds and oozes, and abundant life. Though storms disturb only upper waters, deep regions contain creatures adapted to immense pressure and often furnished with natural light. Ocean currents, especially the Gulf Stream and Kuro Sivo, are presented as great rivers of warm water whose courses and climatic effects arise chiefly from persistent winds and the Earth’s rotation. The book explores the colour of sea-water, arguing that water is intrinsically blue while dust, sand, sea-weeds, and sky-reflection modify its appearance. It describes ice, snow, glaciers, iceberg formation, polar seas, and the circulation of water between ocean and land. It also considers British weather, using a long record from Reigate to argue that good weather greatly outnumbers bad. A central theme is the continuous contest and partnership between land and sea. Rain, rivers, waves, glaciers, and currents erode rock and transport sand, mud, pebbles, and other material into the Ocean. Rivers build deltas; the sea deposits sediments, especially on the continental shelf; and movements of the Earth’s crust alternately raise land and sink it beneath water. Stratified rocks, including sandstone, are described as water-laid records of earlier seas. Ripple marks, raindrop impressions, and marine fossils on mountains show that land and sea have repeatedly changed their relations. The work considers cooling, crustal shrinkage, earthquakes, volcanoes, and differing theories of the Earth’s interior as forces shaping continents and ocean basins. Ocean-building is then shown to depend not only on mineral sediment but on life. Chalk consists largely of innumerable minute shells made by Foraminifera, jelly-like “First Animals” which extract lime from sea-water and form carbonate-of-lime skeletons. Their dead shells accumulate as Globigerina ooze, though deep water can dissolve them before they reach the bottom. Flint is linked to Diatoms, microscopic vegetable forms that construct exquisite flinty cases, and to other silica-forming organisms. Sea-weeds range from invisible Diatoms to immense kelp forests, but ordinary plant-life is confined to lighted waters. Coral reefs and islands are created by communities of coral-polyps, soft jelly-like animals that secrete stony skeletons. Waves break, grind, and cement coral remains into reef-rock, while sand, seeds, plants, and mould gradually make islands habitable. Atolls, fringing reefs, and barrier reefs are explained, along with rival accounts of how reefs rise from depths beyond the range in which living coral can survive. An imaginative descent through the sea gathers together these discoveries: sunlight and sea-weeds vanish below the hundred-fathom limit; cold, darkness, mud, deep-sea animals, luminous creatures, wrecks, and submarine mountain slopes replace the familiar surface world. The Challenger’s soundings and trawls establish that life exists from the surface to even the greatest known depths. Dead plant material falls from upper levels to feed deep creatures, while animals also consume mud and ooze and prey upon one another. The later chapters survey several great groups of ocean animals. Medusæ, hydroids, sea-anemones, and jelly-fishes are described as lowly but often beautiful creatures, many equipped with stinging threads and phosphorescent light. Starfishes, sea-urchins, molluscs, oysters, pearl-makers, limpets, cuttlefishes, crabs, lobsters, shrimps, and prawns illustrate the varied armour, habits, intelligence, and warfare of marine life. The giant squid appears as a formidable deep-sea predator, yet is itself prey to the sperm whale. Crabs display remarkable navigation, growth by casting their armour, and, in spider-crabs, the deliberate-looking use of sea-weed and sponges as disguise. The text finally turns toward the innumerable world of fishes, introducing them as an essential and densely peopling presence throughout the Ocean.

By Agnes Giberne · First published 1878 · Genre: Nautical Fiction, Adventure, Historical Fiction · 26 chapters · 63,590 words

First lines

"How cheery are the mariners, / Those lovers of the sea, / Their hearts are like its yesty waves, / As bounding and as free. " -- P. BENJAMEN.

"Therefore also do men entrust their lives to a little piece of wood. " / _Wisd. of Sol._ xiv. 5.

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The Mighty Deep is listed on Textopian as a novel by Agnes Giberne, dated 1878 CE.

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Genres

Tags

ocean · adventure · exploration · voyage · maritime · isolation · resilience · mystery · drama · romance · human spirit · conflict

Contents

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