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Meet the Rough Scientists

Capraia Diary: Mike Leahy



Sunday 26th September

Day 2, and I got up early and ran up to the prison again instead of taking the Land Rover. This time I could get on with my work. In a way this was pretty selfish behaviour, because the previous night we had been on a foraging tour, and had found some big barrels, and a pallet. I should have helped load them onto the Discovery, but forgot, and left the crews to carry the can (literally). On arrival there was some concern over the nature of liquid that had been stored in the barrels. Would they blow up if heated? One clearly smelt of diesel, but the other was a mystery; strangely familiar, but not quite right. At first I thought it was paraffin, but after my mind drifted back to the good old days when I worked in a garage workshop, I soon changed my mind to engine degreasant. A strange thing to find on such a tiny island.

Who would have used such a large barrel of the stuff? The important thing was that there was little risk of explosion once the barrels were half-full of water. Petrol could have been lethal.

working on day 2

I busied myself making a steam wheel, a bit like a mini waterwheel. Of course it was not exactly a turbine, but close enough. Then I tried it out by sticking it on the axle of the generator and aiming a jet of steam from a kettle at it.



showing Kate's progress so farNo joy! To maintain an efficient magnetic circuit I had made the armature from some magnetic, but very heavy, sections of scaffold pole. This, added to friction from the simple wooden axle and bearings, made turning the generator a difficult business, so I tried to redesign the steam wheel.



Vanessa chopping woodStill confident that I could get enough power from steam under very low pressure, I persuaded Vanessa to give up helping Jonathan and help me build a bloody great fire to generate much more steam.



Jonathan at workIn the meantime, Jonathan was facing the opposite problem. Wind would readily turn the sails of his windmill, but his tiny generator needed lots of speed rather than turning power (torque) if it were to work, and at this point it was producing no electricity at all.



Eventually I finished my modifications and carried the generator around to the huge twin fires that Vanessa, and most of the film crew had built. The first thing that struck me was how much wood is needed to heat up the two 205 litre barrels of water.

pouring water into barrels working hard

The second was how crude the steam delivery hoses were. With no means of precision engineering, combined with my slapdash approach, it was going to prove difficult to sort out the details. True to form the very roughness of construction b******d the attempt and I couldn't persuade the generator to turn for longer than a few seconds. More to the point, I was facing revolt. Vanessa, both film crews, and our esteemed producer could not keep up with the demand for firewood, and the steam and smoke were pissing everyone off.