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Capraia Diary: Mike Leahy

Saturday 25th September

Three months to Christmas. What an awful thought, but at least I didn't have to make any more dye. More to the point, I had an enjoyable project to look forward to. Jonathan and I were to attempt to generate electricity. I got up at a quarter to six and walked up to the prison in order to get some time on my own. Although I was tired, I enjoyed it immensely, and towards the top, where the track became smoother I ran. On reaching the prison, I took off my sweaty vest and hung it up to dry. I was meant to have bought a second set of matching clothes for [episode 9] but had not found time, and the vest was the only piece of clothing I had that wasn't plastered in brand names.

I chilled out on one of the prison walls watching the sun struggle over the horizon, and it wasn't too long before I heard the dulcet sounds of the Land Rovers' diesel engines pulling up the incline.

starting work

Time to get going! My idea was to make a generator which produced direct current (DC), following the design of some early automobile units in which a coil of wire, supported on an armature is rotated within a magnetic field.

working on the generator

In fact, most of my work on the island was based on my previous career as a mechanic, rather than my current one of molecular biologist / virologist. Even so, both are linked by a common thread: the desire to find out how things work. Jonathan, on the other hand, was to make a very simple (and in my view) small alternating current (AC) generator.

Jon explaining his designHis design incorporated a stationary coil of wire and he was going to pass magnets close to it, thus forcing the magnetic field across the conductor. Although his was an elegantly simple design, I was confident that my generator would function far better.

To get the armature or magnets turning we needed some form of motive power. Jonathan opted for wind power, but I fancied trying something different for when the wind wasn't blowing.

starting on the windmill Jon and Vanessa starting the windmill

As there was no running water close to the prison, I thought that I would try to build a simple steam turbine. As I built my generator, Jonathan started on the windmill.

His generator was an integral part of the windmill's structure, and could not be built in isolation, whereas I could build my generator on its own, and make sure that I could produce electricity before coupling it to a power source.

Vanessa helping my generator

By the end of the first day I had more-or-less finished the generator, and knew that it was whacking out about 6 volts and a good few milliamps. On the other hand, Jonathan was halfway through building the windmill, and had no idea whether his design would be successful. To be honest, I thought that I was almost there, and didn't think that there would be any problem turning the thing. How wrong could I be?