Our Oceans - I

Chapter 1: Oceanography - The early days when "nothing lived in the deeps"

"Every gap in the noble little army of martyrs striving to extend the boundaries of knowledge in the wilds of Australia, on the Zambesi, or towards the North or South Pole, was struggled for by earnest volunteers, and still the great ocean slumbering beneath the moon covered a region apparently as inaccessible to man as the 'mare serenitatis'."

That is how Sir Charles Wyville Thomson, Scottish scientist and naturalist described the state of our knowledge of the deep ocean in his 1874 book Depths of the Seas

Thomson, who organised the greatest ever deep ocean expedition (the Challenger Expedition 1872-76) was concerned that, up till that time, there had been a widespread belief in Forbes 'Azoic Hypothesis' or "lifeless deep" theory. This theory had been given widespread approval after Edward Forbes scoured the depths of the Aegean Sea and concluded that...

"As we descend deeper and deeper into this region, the inhabitants become more and more modified, and fewer and fewer, indicating our approach to an abyss where life is either extinguished, or exhibits but a few sparks to mark its lingering presence."

But this flew in the face of the findings of Capt John Ross (later Admiral Sir John Ross). As early as 1818, Capt Ross had manufactured a "Deep Sea Clamm" which he used from his ship, HMS Isabella, to bring up four samples of the sediment from the bottom of the ocean at depths between 850 and 2000 metres. These contained crustaceans, corals, shellfish, worms and a magnificent basket star (asterias caput-medusae).

At the same time that Edward Forbes was propounding his Azoic Hypothesis - based on poor trawling techniques in a depleted ocean area - Capt James Clark Ross (nephew of John Ross, and the man for whom the Ross Sea is named) led the British Antarctic Expedition of 1839-1841.

Working on HMS Erebus and HMS Terror at the latitude of the Antarctic Circle, he reports that...

"Becalmed for two or three hours after noon; the dredge was put over in 270 fathoms [c 500m] water and after trailing on the ground for some time was hauled in... beautiful specimens of living coral...Corallines, Flustrae and a great variety of invertebrate animals, also came up in the net showing a great abundance and variety of animal life"

Considering the findings of his Uncle, on the other side of the world in Antarctica, James Ross was strongly opposed to Forbes' Azoic Hypothesis - going so far as to say in his published report..."It was interesting

Twenty years after Ross' expedition and assertion against the Azoic hypothesis, George C Wallich, on board HMS Bulldog, records in 1868 dredging 13 starfish from 2500 metres - that's two and a half kilometres deep - down in the North Atlantic.

There had been some debate about whether Capt John Ross' Medusa-head starfish (asterias caput-medusae) had "swum onto the trawl line at some much shallower depth than the 850m they were dredging". This would have given Forbes Azoic Theory a little more room to wiggle in, but Wallich's samples (including 15 samples of stony coral - Caryophillia) were recovered attached to a telegraph cable 2500 metres down.

Then we come to the evidence of the Norwegian oceanography Professor, Michael Sars, who trawled the deep fjords of Norway bringing up 427 examples of species living at these - hitherto untenable - depths.

Wyville Thomson met Sars in 1866 and saw samples of crinoids brought up by G.O. Sars, the professor's son, from 825 metres. There were also Rhizocrinus of a new species that Sars named Lofotensis, being found at the Lofoten Islands near Norway's Arctic circle.

It is possible that Sars' discovery was the catalyst that drove Thomson, together with William Carpenter, to persuade the British navy to lend them two ships, HMS Lightning and HMS Porcupine to run a pilot exploration in 1868. That expedition would be the precursor to the great "Challenger Expedition" of 1872-76.

Our Oceans


Chapter 1: Oceanography - The early days

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