Not all naturalists were content to base their knowledge of the underwater world on the scraps that filled their dredges and entangled their grapnels, but 200 years ago diving equipment was too expensive, too difficult to use and too dangerous to tempt even the most curious beneath the waves.
Most diving outfits of those days were little more than complicated ways in which to drown. Often simple devices are the best, and the simplest diving equipment- the diving bell- had been known since at least the 4th century BC. Once sufficiently powerful pumps were available, the air supply trapped in the inverted bell could be continually replenished from above.
Large bells proved their worth for salvage work in deep water, but naturalists and explorers wanted to see what the underwater world looked like.
The solution was a portable diving bell like a bucket that would fit over the divers head, allowing him to breathe, and with a glass window revealing the view. Soon marine biologists were donning buckets and milk churns and walking beneath the waves.
Henri Milne Edwards was born in Belgium, the 27th son of an Englishman- surely some sort of diving record in its own right. He was a medic by training, but switched to zoology and by the 1840s became a professor at the University of Paris.
He had often had the desire to descend in a diving helmet and to be able to examine at leisure the submarine rocks inhabited by those whom I would like to make the object of my researches. His friend Colonel Paulin, Commandant of the Paris fire brigade, had devised and built a helmet to allow his men to pass through smoke and fumes. Milne Edwards persuaded him to construct an improved device suitable for diving.
In 1844 Milne Edwards and his companions set off for the clear waters of Sicily on the first diving expedition undertaken by marine biologists. They fell victims to all the horrors of seasickness, aggravated by the smell of the crew, armies of whirring cockroaches that emerged at night from every crevice in the boat, and the horrific concoctions devised by the ships cook. After this, the underwater world would hold no terrors.
The diving gear was a large, open-bottomed metallic helmet, with a hose snaking up to a huge double forcing pump on the surface. The helmet had a glass window and its cushioned rim allowed it to sit comfortably on his shoulders. Held down by lead sandals, the portly professor descended into the sea.
Milne Edwards was armed only with a pickaxe and determined to pursue marine creatures into their most hidden retreats. While the crew laboured over the pump, he strolled below in the enjoyment of perfect liberty of action, stopping to examine the fissures of the submarine rocks which thronged with molluscs, worms and zoophytes. He stayed below for half an hour at 4m.
If anything goes wrong with a diving bell the diver can duck out from beneath, shed the helmet and swim to the surface- unless, of course, he is wearing lead sandals. Milne Edwards had secured a line from his harness over the ships yardarm so that in an emergency he could signal with a tug to be hauled up.
But when he was accidentally retrieved in a hurry, the yardarm cracked and he plummeted back to the bottom. Several of the crew leapt in to save him, forgetting that they couldnt swim. They too had to be rescued.
During the three-week expedition Milne Edwards made many dives, going deeper and staying longer. He claimed that it would have been simple to descend to much greater depths had not the inadequacy of the life-saving facilities on the fishing boat made me think that it would have been imprudent to try. He became the first marine biologist to describe living subtidal communities.
He was impressed by his first experience of the underwater world to the extent that he never dived again. But in an age when many biologists were content to pore over pickled animals in jars, or dried plants, he was a true naturalist prepared to endure danger and discomfort to see how organisms really lived. And others would follow.
In 1882 the German botanist Berthold published a detailed catalogue of the seaweeds of the Gulf of Naples, after using an open helmet to collect subtidal ones.
All the early devices had been open helmets and even when the sealed hardhat suit became the standard, commercial divers working in warm, shallow waters often dispensed with the suit and just used the helmet.
W S Dunn probably saw them doing this while working on the railroad extension through the Florida Keys. He designed a simpler open copper helmet not very different from that worn by Milne Edwards, and marketed it with his partner, W F Miller. In 1915 the director of the Marine Biological Laboratory of the Carnegie Institution, on Dry Tortugas in the Keys, bought one for the use of visiting researchers.
It was immediately taken up, or rather down, by Professor W H Longley, who published several early underwater studies on fish behaviour. He also became fascinated by underwater photography, taking black and white shots of moving fish in natural light as early as 1917. Six years later he took the first underwater shots in colour, using slow film the colour of which was derived from millions of embedded grains of tinted starch.
To provide sufficient light, he exploded 1lb charges of powdered magnesium on an opened-bottomed raft floating above. The blast was equivalent to 2400 flashbulbs, the brightest light ever used for underwater shots. It was almost more than human nerves could stand; certainly more than the raft could stand, for one explosion blew it to smithereens.
Roy Miner was a curator at the American Museum of Natural History, his task to create marine-life exhibits. So he bought a Miller-Dunn helmet and set off on expeditions.
The museums curators were stout fellows in those days. One was bitten by vipers, another pinned to the ground by the tusks of an enraged elephant, a third throttled a leopard with his bare hands before it could rip him apart.
Miner too almost had an adventure; he was once stung by a jellyfish and shouted at a shark. But that was about it.
He decided to construct a full-sized replica of a coral reef in the museum. So from 1923 until 1936 he systematically demolished a reef off the Bahamas, sending 10 shiploads of coral back to New York to be reconstructed in the museum into a reef 6m high, occupying more than 1000sq m and inhabited by 500 wax fish. If he had any qualms about such wanton destruction of the natural reef, he never voiced them. Nor, in those days, did anyone else.
Another enthusiast for the diving helmet was William Beebe. He was an ornithologist who planned to make a single diving expedition, but as he admitted, one millionaire gave him a yacht, another millionaire gave him a yacht and the Governor of Bermuda gave him an island. So he spent ten years under water.
Beebe is best remembered for his descent in the Bathysphere half a mile down, five times deeper than anyone had been before But earlier, in 1925, he had entered what he called the kingdom of the helmet and enjoyed the delights of dangling.
At first he thought the equipment too simple to be any use. But like most divers he soon became laden with gear: pads of waterproof paper for notes and nets and harpoons for collecting specimens.
His aim, as with most naturalists in those days, was to collect and identify as many creatures as possible. He would smash open coral to attract fish for study, claiming that a desert of animal life could be converted into a populated oasis with a few strokes of a crowbar.
Sometimes dynamite came in handy. He was rapidly becoming more of a marine than a marine biologist. His gentler colleagues took down weighted easels to paint the wildlife.
Beebe became famous; he broadcast from 660m down and wrote dozens of best-selling books. Few have matched his poetic descriptions of the magic of being under the sea.
Beebe urged his readers not to die without having borrowed, stolen or made their own helmets, to glimpse for themselves this new world.
In 1937 Hans Hass did make his own helmet, copying the illustrations from Beebes books. He trudged across the Danube under water, descended to 18m in the Adriatic, then went diving with his student friends in the Caribbean.
Hass met sharks aplenty and back in Vienna sold prints of his underwater photographs and went on a lecture tour. His first lecture was spiced with the appearance of a muscular friend wearing bathing trunks and the diving helmet and brandishing a harpoon.
It was a sensation, but the embarrassed friend refused to appear again, so next time the usher filled the breach- to overflowing, for he was short, rotund and pink. His entrance was greeted with uproarious laughter from the audience.
Unfortunately, he had removed his glasses and the window on his helmet steamed up. Blind and waddling out of control on finned feet, he tottered into the auditorium and almost lanced an hysterical dowager with his harpoon.
The British bucket brigade was not to be outdone. In 1928 the cream of our young marine biologists set off on a year-long expedition to the Great Barrier Reef. They took a helmet made from a milk churn. with two front windows angled so that if the diver tried to look through both simultaneously, he fell over.
The glass frequently steamed up and when the diver leaned forward, unless he judged it just right, the ocean swilled in and he would almost drown.
Jack Kitching became the first biologist to do research under water in Britain, using a home-made helmet off Devon in 1937. The lead weights that kept it in place were so heavy that they could not be attached until the diver was submerged.
Even when Kitching explored kelp forests in Scotland he wore nothing warmer than a rugby shirt, so it was difficult to withstand the cold for more than 20 minutes at a time. Frequent diving led to a greatly increased appetite for sugar and treacle, which he retained for the rest of his life, whether diving or not.
His helmet had an internal telephone, with its microphone encased in a toy balloon. The intention was to dictate notes to the surface where they would be written down prior to publication, but the message he most frequently transmitted was: More air! More air!
Armed only with hedging shears to cut his way through the dense kelp, like a ghostly gardener, he trudged down to 12m through the forest into a park of more widely spaced plants.
The first biologist to see the kelp forest under water, he was not content until he had described the distribution of the kelp and all the organisms that lived on and under it. Using a photocell and filters he recorded the amount and quality of light at different depths and beneath the canopy. It was an astonishing piece of work for its time.
For many of the helmeted pioneers, the sea was a place to be enjoyed and exploited. Miner destroyed a reef, Beebe collected specimens by the dozen, Hass was an avid spearfisherman, as were Cousteau, Tailliez and Dumas.
In time they turned to worthier adventures: Hass to photography, Beebe to conservation. But without their swashbuckling beginnings, we would not now enjoy the freedom of the seas, and buckets would have merely carried water, not explored beneath it.