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Meet the Rough Scientists

Carriacou Diary: Mike Leahy



Day 9 — Anti-bacterial Cream

Rough Science biology lab equipmentI'm pretty positive. We are given the challenges. At last I can use science that I have some experience in.

OK, I'm a virologist not a microbiologist but I do use bacteria as 'tools' and am comfortable with the techniques used when growing them. My challenge, together with Ellen, was to make an anti-bacterial cream. The first task was to grow bacteria. That would be difficult enough without even thinking about stopping them grow. Just to clarify a point — although in the TV programme we say anti-bacterial or bacteriocidal. The test we plan to use will only identify bacteriastatic agents — in other words, those that prevent bacteria from growing rather than those that kill them.


Day 10 — Anti-bacterial Cream

Mike and Ellen by the biology labI got to the factory to check the bacteria — didn't look like they had grown very well. Bummer! The bottle didn't smell at all. This wasn't a good sign. The day hadn't started well either because I was covered with bites around the back of my legs and butt. Even so, I fuelled up the autoclave and sterilised the plates we would use to hold the agar. An autoclave is like a pressure cooker. It allows a saucepan to operate under pressure when heated. This raises the boiling temperature of water. If the pressure is raised to 15 [pounds per square inch] water boils at 121°C (about 250°F). This was the only fact I knew — a weird imperial/metric mixture. With Kathy I worked out that using a 75mm (about 3 inches) diameter tin I could add a 17kg (about 37.5 lbs.) weight to raise pressure to allow a boiling temperature of 107°C (about 225°F) or, if I could find a 50kg (about 110 lbs.) weight I could get a boiling temperature of 121C. This would be difficult — imagine balancing a teenager on a can of backed beans. If we had used a slightly bigger tin (because area increases as a square) we would have had to balance a car or a couple of cows on a can about 15cm diameter. In the end we found a lump of concrete which certainly didn't weigh 50kg but was definitely more than 17kg. Therefore, we guessed that we were getting a boiling temperature of around 110C-112C (230-234°F). It looked pretty ungainly.

Around lunchtime we had a crisis with the agar and burnt some while trying to film. Ellen and I then struggled on with the next batch which, luckily, worked very well. It was all very hectic.


Day 11 — Anti-bacterial Cream

This was day three of the challenge and Ellen and I were well ahead of the game — but only if things worked. If no bacteria had grown overnight we would be stuffed. Steve was concerned — it would have been nice if the bigger projects worked well all the time but they were all quite difficult.

We finally arrived at the lime factory and had a look — not the smartest plates in the world but there was definitely plenty of bacteria. We had real trouble spreading them with the tools available and because it was so hot the agar wasn't setting quite as well as we had hoped the previous day so we weren't expecting perfect results. We would have been happy with any bacteria and we had loads. We would have been even happier if we could see an effect of the bacteriacidal (or more correctly bacteriastatic) agents. Luckily the garlic worked wonderfully. Of course, the plates weren't as nice as they would be in a lab but at least we had a good idea of what we wanted to add to the tests. But ...

1. We were not familiar with the seaweed on the island and as they aren't plants anyway it wasn't really Ellen's department. Next time we could try different species.

2. If the agar were no better, regardless of species, we could have chilled it to make it more solid when we originally manipulated it.

3. A more precise spreader would have made the plates more uniform, but glass blowing/melting was difficult.

4. The media could have been optimised. It was very hit and miss.

5. To get a more defined area of inhibition we could have let the bacterial inoculum 'soak in' or dry a little before adding the anti-bacterial agent.

6. Most important, we could have made titrations/diluted the bacteria or anti-microbial.

The overriding problems were related to our working environment. Labs are air conditioned, for example, but here the temperature varied from 27C to 34C (80-93°F) and humidity was sky high. At least the incubation time was about right without the need for an accurately regulated incubator. But wind and dust were problems and it was very difficult to keep things clean.

In addition to the microbiology project, a big one in itself, I also had to predict weather using local weather lore. I was worried about this because much of it was b*llsh*t and I had no idea what tropical weather was likely to be and how to predict it. After chatting to local sailors and fishermen I found out that it was unpredictable and you could only really work out weather about two hours ahead if you were lucky. Of course, this excludes the relatively reliable wet and dry seasons. Apart from telling the temperature using a cricket, I just took the opportunity to illustrate chaos theory and point out how difficult it is to predict the weather.

As we approached the end of [episode 2] we were all very tired but keen as mustard. I wanted to finish early — no chance!


Day 12 — Rest Day

Mike and David in the mangrove swampWe return to the mangrove swamp and see a steel band.

I laid in with a hangover. Finally emerged around 10 o'clock ready to leave. I had wanted to show J the swamps because otherwise, due to the filming schedule, he would not see them. In the end, Kathy and Angie came along and David offered to drive. We more-or-less re-traced our steps but this time it was far more relaxed. We also had time to climb across the mangrove roots which were amazingly strong. This was probably because they are arched shaped. We chilled for a while before returning to have a good sleep. That night a steel band played at the hotel. It was awesome and most of us danced 'til we dropped. Shell, Amocco and Texaco.


Day 13 — Rest Day

Another great day off.

Kathy sorted out a sailing boat for those who were going back home during the break. I just did some e-mails and chilled. Filming for 3 days genuinely makes me very tired.


Day 14 — Clocks

Coke, lines, razors and bongs

Mike B and Mike L explain their plans to KateThe challenge — clocks. Could be boring. Mike and I decided that we would have a laugh and got stuck in — calabashes, sundials, water, compasses, the lot. We wanted to make something that would work, but with an element of humour.

Why equinoctial? Why a syphon? Why not a mechanised wrist watch? I'll explain later. I had the mother of all hangovers but tea and cola — spot on.


Day 15 — Clocks

It nearly goes Cerano de Bergerac.

Because we had been filming late the previous evening Mike, myself and the crew left at about 8.30am for the lime factory — a gorgeous lie in which was needed because of the racket made by a regatta party the previous night at the hotel.

Mike's sketchOur first job was to lift a huge barrel up onto the top of the lime juice making machine. At first, I thought it was a mad idea but I could see the funny side so we decided to have a go at it. This would need the whole team and Sarah, the director, said that I should take charge of the project. I really wasn't confident about this because the other members of the team can be real 'loose cannons' and Ellen in particular will never do as she is asked.

We set up ropes so that we could lift the barrel and it all went very smoothly at first. In fact, the barrel must have been in position within a minute at most. Up until now the only problem had been the normal fighting for attention among the other contributors who all (Mikey apart) wanted to be in camera shot. Ellen wanted to climb up the Dr Zeus machine but there really was no need. I asked her to pull on the rope with J, Kathy and Kate but she wasn't at all pleased. Sarah began to become irritated because no-one ever did what they were asked and everyone seemed to have better ideas and all of them wanted to be heard — bedlam.

Then things began to go pear-shaped. One of the big wooden beams that held the tank up became dislodged. It was still hanging up there but Mikey, who was at the top, looked to be in a perilous position. We had a very quick debate and I asked Jonathan and Kathy, both good climbers, to lend a hand while Ellen and Kate held the ropes. They climbed parallel to the beam and tried to pull the beam back in place with rope — no good. Eventually, the beam fell and we were stuffed. More to the point, Ellen who thought that she should have been consulted more, got a strop on. She later claimed that it was because she was worried about safety but it really appeared to be because she had been told what to do by Sarah and hadn't been doing much for the cameras.

Trigger designs — nightmare. It's very difficult to get them to work efficiently with all this friction. Wood and six inch nails don't compare to 17 jewel actions on Swiss watches.


Day 16 — Clocks

Mouth ulcer hurts — no beer for two days.

Task 1: calibrate water clock &151; tedious.

Had fun filming but Paul swallowed some foul water getting a syphon going &151; it was full of Rasta pee. Put up two further tracks for the coconuts. Mike sings "I've got a lovely pair of coconuts". It's all very silly and damn hot. I begin to feel a bit nauseous from the heat. Thank God for tea and cola. Mike and I did a silly mad professor scene. It looked pretty cool but I felt a little uncomfortable doing it. The clock seems to be working OK and everyone is getting on fine. Ellen's kite won't quite fly, the transmitter transmits, but only 10 to 15 feet, and the clock, whilst working in theory, doesn't tell the time. That's the beauty of edit suites.

Q. Why an equinoctial sundial?

A. Sundials, like the ones often found in gardens — have unequal gaps between the shadow cast each hour. If we make sure that the gnomen (pointer) is aimed at the North Star and we use a ring to read the time which is positioned at the same angle as the equator of the earth, the gaps between the shadow cast each hour will be equal. Cool!

Q. Why use a syphon rather than punching a hole in the bottom of the top barrel?

A. If we use a syphon the flow is determined purely by the height that the water falls regardless of how full the top barrel is.

Q. Why not make a mechanical wrist watch?

A. Too bloody difficult with stone-aged technology.

3pm

No vice, no decent metal drill = bloody nightmare, especially in the heat. The humidity makes everything so hard, and the filming makes work even harder. I get dizzy and because I am nervous of heights and Mike is a good climber he works 'up top' in the main. There was potential for a real disaster.

It appears that my dizziness wasn't just the heat — I'm rough. Even so, it's great fun working with Mikey B. As we continue to make rails for calabashes and coconuts, boats sail and motor past on their return trip from the regatta. We try to roll a coconut all the way down a set of rails again but as it hits one of the joints in the bamboo, it falls to the ground. By the end of the afternoon over a dozen coconuts are broken but the unexpected feast is popular with the rest of the team and crew. In order to make a side rail, a bit like a banister, to keep the coconuts on the straight and narrow I try to cut the stems off the side of another piece of bamboo. There's no vice so I try to wedge the stuff in the Zeus machine. It all goes OK until I get loads of sharp bamboo sawdust in my eyes. Agony for half an hour as I try to wash it out using drinking water. Finally, can see again. I have never missed anything as much as a vice — G-cramps [C-clamps] don't come close and I've risked my fingers/eyes/legs once too often. Last series I ran a drill into my hand because we had no vice. I don't want a repeat. Mind you, that's the least of my worries after the beam fell down and the filthy water we use for siphoning is even more of a risk (as I was later to find out).

Kate told us how we were going to use our 'inventions'. At 3pm I was to use my 'moderately' accurate wrist watch to tell Kathy and Ellen the time. Then Ellen would fly her kite (which didn't fly so was held up with bamboo) to alert J and Kate (who were all of 30 metres away) to receive a message. At the same time Mkey B could tell the pair because the water clock should chime 3pm. It all sort of worked after a lot of panicking. Initially, both transmitter and receiver failed — they were notoriously moody but finally Kathy got the message through: daah dit daah daah dit did dit dit. YES. At last it worked. The water clock was iffy because of the difficulty in making a decent 'trip' mechanism at height and because we didn't have enough time to calibrate it. The kite was erratic but the solar clock, solar watch, transmitter and receiver all went well enough. Even so, the range of the transmitter and the poxy local Christian radio station which interfered with our signal rendered the transmitter more or less useless. It definitely highlighted the difficulties faced by the early scientists.