Homage to Gaia (35 page)

In the early autumn, I made a journey to Barry Docks near Cardiff in Wales to see the
Shackleton
and negotiate the small amount of lab space I would need with the chief scientist of the expedition, Peter Barker of Birmingham University. Barry Docks are huge, dismal and all but deserted, like a theme park devoted to Britain’s past industrial history. The presence of Butlins Holiday Camp at the edge of the near-deserted docks increased the theme park atmosphere. There were railway sidings full of rusting steam locomotives; some had shapes I had never before seen. There were a few banana ships moored at one dock so I suppose it was not entirely dead, but grass and
yellow-flowered
ragwort filled the gaps along the railway lines. I could find no one who knew where the
Shackleton
was moored, so I drove around this vast maze until I saw a small one-storey building with an NERC sign above it. They directed me to the mooring place, which they said was beyond a group of disused cranes. I looked for a ship’s mast and funnel but could see nothing. I parked my car and
walked to the edge of the dock. There below me, like a child’s toy ship, was the small vessel. It was tiny compared with the banana ships, but soon it would take me to South America.

I climbed down and boarded. The
Shackleton
was a converted Baltic coaster of a few hundred tons displacement, powered by a diesel engine. Part of the conversion was a bow thruster, a propulsion mechanism in the ship’s bows in addition to the main propeller, which made the ship unusually manoeuvrable and no doubt was required for the time it spent among the ice floes. The lab area was at the deck level and spacious. They gave me about twelve feet of bench with wooden drawers and cupboards beneath and a 230-volt electricity supply with normal three-pin plugs at the bench top. This was all fine by me. I never could see the point of bulky apparatus in science unless it was truly necessary. The ship was in the midst of preparation for the voyage and in an untidy and unwelcoming state, rather like a house full of builders and decorators. I returned to my car and drove back to Bowerchalke. As I drove through the
Gloucestershire
countryside, I could not help wondering what the voyage would be like. The view of the ship at Barry made it look uncomfortable. Almost, it seemed to me, like trying to do experimental science in a Tube train full of rush-hour passengers.

November came and I made my farewells to the family and travelled to stay the night at a small hotel in Barry, from which I boarded the ship next day. It was not due to sail until the evening tide and so there was plenty of time to set up the equipment and try it out. The ship had now been transformed since my previous visit and looked tidy and shipshape, and moving around was no longer an obstacle course strewn with large wooden crates and thick cables. The ship’s mate Nigel Jonas took me to my cabin, which was far better than I had expected. It was at the level of the bridge and was where the ship’s officers had their cabins. I was in the ship’s sickbay, normally the home of the ship’s doctor. It was a roomy and comfortable cabin, provided with a desk and all that I would need.

Lunch was in the ship’s dining room just beneath the bridge. It was a cosy, pleasant room and gave me my first taste of the food we were to enjoy during the next three weeks. Like most English ships of those times, the quality of the food served was excellent. As a maritime nation, we understood well the need for an interesting and varied diet to relieve what to many sailors is the monotony of a long voyage. After lunch, I made a few measurements of the CFCs and other halocarbons 
in the air of Barry docks. The equipment was working well, but the air was rich with all kinds of chemicals that could be recognized by my ECD; not the background air that I wanted to measure.

Soon after dusk fell the gangway was detached, the moorings
loosened
, and, as we slipped away from the Barry docks, once again that most estimable of emotions overcame me—the sense of
overwhelming
contentment that fills me when I am on a ship that has just set sail. Sometimes on a plane, especially after a fraught and delayed
departure
, there is a feeling of relief as it leaves the runway, but that is a pale imitation of the joy of severing contact with the land which is the gift of a ship’s departure. There is something good about becoming, even temporarily, part of a proper-sized human community. November in 1971 was a quiet, slightly foggy time and our passage down the Bristol Channel to the Atlantic was easy, just the gentle lively roll that came from the Atlantic swell. I think that I am immune to seasickness, so the ship’s motion was always for me something to enjoy, to lull me to sleep when the time came to retire to my cabin.

At dinner that evening I met our captain, Shelby Smith, and the ship’s officers. They had made sure that we had some good wine to drink with our meal. That night I retired early, replete and looking forward to an exciting and rewarding voyage amongst good
companions
. I rose early next day and took my first sea and air samples as we travelled somewhere near Cornwall. The wind was drifting from the east and the CFC levels were still high. I took my air sample at the ship’s bows using one of the two large holes through which the anchor chains passed. A wind usually blew through these holes and made them an ideal place for taking clean air samples. Compared with other research vessels the
Shackleton
was
free of chemicals but I had to keep in mind the ship’s refrigerators that might be leaking CFCs. Moreover, some of my companions might be using aerosol cans of shaving soap or deodorant powered by CFCs. I drew the 5-ml sample of air into a clean glass hypodermic syringe with a needle attached. I did this several times to make sure that the sample was clean air and not some memory of past air residing on the glass surfaces of the syringe. I took my filled syringe back to the ship’s laboratory, injected the air into my gas chromatograph, and watched the peaks appear. First, came the oxygen of the air, a large off-scale deflection; soon after came the peak for chlorofluorocarbon 11, then a tiny pair of peaks of methyl iodide and carbon disulphide, and finally a broader peak of carbon tetrachloride.

All was going well and I went in for breakfast. This was full English fare: cereals, porridge, all kinds of eggs, bacon, sausages, fried bread, and so on, followed by toast and marmalade and washed down with lots of tea or coffee. I rapidly decided that cereals and a slice of toast were all I needed on this comparatively sedentary voyage. At first, there had been a rush to set up and make sure that everything was working but now, after eating, I had time to look around the ship. I wandered over to the other occupants of the main laboratory, a party of scientists who were making a gravity survey in the southern oceans but were also taking measurements as we travelled down the Atlantic. Compared to mine, their apparatus and their team were substantial. I got to know them better when, in mid-voyage, the ship’s technician and I
discovered
for them the source of mysterious and disturbing signals that appeared without warning in the middle of their charts and interfered with their measurements. It was the Morse code of the ship’s radio transmitter picked up by their ultra-sensitive electronics. We cured it with some aluminium foil from the galley, which we used as shielding.

Another scientist on the ship occupied a sizeable lab closer to the bows; he was Hans Greese, a student of the German scientist,
Wolfgang
Seiler. His lab was festooned with a beautiful and intricate array of blown glass and in it he was measuring atmospheric carbon
monoxide
(CO). The student was from the Max Planck Institute at Mainz in Germany, a famous scientific centre for atmospheric research run by the distinguished scientist, Christian Jünge. Most of us think of carbon monoxide as a poisonous gas that comes from incomplete combustion and which is a favourite for suicides, since it is odourless and painless to breathe. Carbon monoxide, strangely, is a natural substance present in fresh air everywhere in the atmosphere of the Earth, but at an average level of only 80–90 parts per billion. It comes from the natural oxidation of methane gas in the atmosphere, and from the combustion of fossil fuels. Hans’s apparatus collected,
separated
, and analysed this substance. His objective was to discover the difference in abundance of CO between the northern and southern hemispheres, just as I was doing for the CFCs, but his work was hard and unremitting, and only rarely had he time to leave his laboratory. I felt almost ashamed by the ease of my measurements and the way they allowed me time to wander around the ship and wonder about the ever-changing scene.

By mid-morning, it was time to take the first water samples. A research ship like the
Shackleton
has a pump to draw in fresh seawater
from the bows so that the scientists aboard have a continuous sample of the sea the ship passes through. My first sample of this water was so laden with chlorine and sulphur compounds that it overloaded the chromatograph and I could make no analysis. I was sure that these substances were not in the sea itself but were contaminants coming from the pump or the pipes through which the water flowed. I could see no way to get a truly clean water sample from this source, so I tried collecting sea water by tying a small bucket to a rope and dropping it over the side of the ship. This was foolish, for the fierce pull of the rope nearly dragged me overboard, and I should have calculated that a bucket dropped into water flowing past at 14 mph exerts a pull of over 100 pounds. Contritely, I asked the ship’s technician if he had a smaller vessel I could use. Lab vessels such as beakers were much too fragile; saucepans too difficult to manoeuvre on our rope. Then suddenly we wondered whether we could use a teapot? Sure enough, the galley had an old aluminium teapot now retired from use. This we tied to our rope, and everything was easy from then on. Every day we lowered it into the sea and used it as a source of surface water samples.  

The sight of our teapot sampling stirred the serious-minded
company
of scientists; some were derisive of such low technology, others were appalled. One of them, who was not experimenting until the ship reached Antarctica, said to me, ‘You know, the ship has proper Nansen bottles for water sampling and I’m sure the captain will stop to let you sample down to lower depths.’ Captain Shelby Smith was more than willing to do this, and at frequent intervals we stopped to lower ships’ bottles by cable down to depths as low as several hundred metres. Again, I was frustrated in my measurements, this time by the rubber closures of these bottles. The rubber absorbed and later released any volatile chemicals in the air around it. This memory of past atmospheres contaminated the water samples from these Nansen bottles. We tried several tricks. Taking the rubber and boiling it in water for hours helped, so did leaving the bottles exposed open to the sun and air on the deck before use. In the end, we used bottles without the rubber closures. They leaked, but not enough to prevent them serving my needs. Up until this voyage, marine scientists had been interested only in the inorganic constituents of seawater—things like salt, acidity, and other minerals. The rubber-sealed Nansen
bottles
were fine for this need. No one had anticipated the need to collect volatile organic vapours like the CFCs and DMS, and so they never designed bottles for this purpose.

It stayed cool as we passed the African coast. We pulled into a deserted harbour in Mauritania for some ship’s repairs, but otherwise saw little of the land until we passed the Canary Islands. The captain told me that for much of the voyage we would be following the track of the
Beagle
that took Charles Darwin on his journey of discovery 120 years earlier. It was a thought that inspired us all to make this voyage significant in some scientific way.

The next day dawned hot, a sudden transition from the mild oceanic air we knew so well at home in England to tropical heat and humidity; the air temperature rose from 18° C to 27° C and the
seawater
from 18° C to 25° C. Shortly after this, a younger member of the ship’s crew had a fall that left him in pain and with restricted movement. The Captain came to me and said, ‘You are a doctor. Can you have a look at him and tell us what we should do?’ ‘I’m not a proper doctor,’ I said, ‘I’m not qualified to practice or treat people.’ Shelby Smith replied, ‘You are the nearest we have to a physician on the ship and you will just have to do for now. After all, you have a PhD in medicine; surely you can do better than I can.’ We had the boy carefully taken to my bed in the sickbay. He was conscious and his breathing rate and pulse were normal but he had back pain and found it difficult to move. Two things I remembered from my Medical Research Council years were: first, there are only three real medical emergencies—asphyxia, haemorrhage, and cardiac arrest. Secondly, when in doubt, do nothing and seek expert advice. This I did via the ship’s radio. We called Portishead in England and they connected me to the physician on duty. He spoke with an accent, which was difficult to understand over the crackling and fading short-wave radio link, but I gave him an account of the accident and the boy’s symptoms. He replied, ‘It sounds like a spinal column injury. He must go to the nearest hospital as soon as possible. He certainly should not travel the rest of the voyage with its danger of rough seas and further damage.’ Captain Shelby Smith immediately changed course for the nearest port, which was Dacca in Senegal. Here, an English-speaking, French physician examined the boy and then treated his injured back. The captain and the boy returned to the ship and I was able to return to my cabin for the rest of the voyage. The stay in Dacca was brief, but we did enrich our supplies of fruit and fish from the boats that flocked around us in the port.

We started towards the Cape Verde Islands. That evening at dinner the mate warned us not to wander on the ship’s decks without using
sun block. He said there was plenty of it in the ship’s stores. Sunburn is a serious problem in tropical waters. Typically, we took little notice of this warning and, as we sailed further south, still in the northern hemisphere, nothing in the way of sunburn seemed to happen. Then one day after rising, I noticed that the air seemed different, the parallel streets of cumulus clouds now projected, it seemed, to infinity. The air had, in spite of its warmth, a fresh cleanliness we had not previously experienced. In the night, we had crossed the intertropical
convergence
that separates the air of the northern hemisphere from that of the southern hemisphere. The southern air is clean and unpolluted; the northern hemisphere is always, to some extent, hazy. As if to punctuate this change, suddenly two flying fish landed on the deck behind me as I took my air sample, and I was entranced. These were living things as strange to me almost as dinosaurs. Many others came on to the ship as we sailed along and we had fresh flying fish for dinner that night.