My experiment in electrodynamics

Sweet and lyrical memories of one man's youth, accompanied by an account of a daring and foolhardy experiment in electrodynamics.

Sigfried was my best friend.

Our backgrounds were actually quite different. I was a local lad, born and brought up in the small town where we both lived, and I came from a family who had lived in the area for several generations. Sigi, on the other hand, had been brought to England as a baby by his parents, who had managed to leave their native Poland during the turmoil of the 1940's. He'd moved to work at the same firm where I worked when his previous job, where he had served his apprenticeship, came to an end when the factory closed.

But we had a great deal in common. We were much the same age, in our late twenties,, although Sigi was perhaps a year or so older than me. We were both married, with two young children - Sigi had two girls, and I had a girl and a boy. The kids came to each other's birthday parties. We often went out on family trips together. We actually lived in almost identical bungalows, built by the same builder but in different parts of the town. The only difference was that our homes were 'handed'. Sigi's I thought of as a left-hand version, whilst mine was right-handed. It was really strange to go into his home and see the recognisable, but opposite, layout.

But the main thing that cemented our friendship was the fact that we sat next to each other at adjacent drawing boards in the drawing office of the engineering factory where we worked. This was a large open-plan office which accommodated, together with the Section Leaders, some twenty or so draftsmen. These were mainly of the mechanical discipline, but with just four electrical draftsmen as well, of which we were two. In a factory which manufactured heavy road-building machinery, the main emphasis was always going to be on the mechanical engineering side of things, and we always felt that us 'electricals' were considered by many to be a necessary evil. But, whatever type of work we did, we all of us worked well, and got on well, together.

Sigi and I helped each other a lot in the course of our work. If I had a problem finding a suitable part, he helped me sort it out. If he couldn't get a schematic quite right to do what was required, we'd work it through together. It was a good relationship, it worked really well between us.

But nothing could disguise the sheer boredom that sometimes overtook us, doing the same type of work month in and month out. So it was with a breath of relief when early one afternoon, we saw our Section Leader come over to us, and ask us if we would like to take a couple of hours away from our drawing boards and tidy up the Development Room. Of course it was an instruction rather than a request, but he was a polite fellow and always gave us our work in this manner. The mere thought of getting away from the schematics, assembly drawings and bills of material which occupied most of our time filled us with joy, and so it was with a scarcely-concealed grin of delight that we immediately downed our pencils and made our way to the Development Room.

The electrical assembly and electrical stores area of the factory was located on a mezzanine floor just beside the machine shop. Beneath the mezzanine was the wages office, and some storerooms. After a long struggle, our Electrical Section Leader had managed some time before to persuade the management that a special area was needed to allow him some space to carry out testing and development of new equipment. And so one of the storerooms had been allocated and converted, with a couple of workbenches and some storage racks etc. The room we had been given was windowless, with just an extractor fan for ventilation. Nest door to it was the telephone switchroom, and opposite to our room was the entrance to the wages office.

On reaching the Development Room we found it to be in a right mess. Tools left laying around, parts and equipment strewn all over the floor. Not a five-minute job by any means. But we immediately made a start by implementing what we always referred to as 'Cobbolds Law'. This we had been taught by another of our electrical draftsmen, who went by the name of Cobbold. Apparently he had developed this law whilst serving in the Royal Air Force. 

Basically what it recommended was that you get most of the work done, up to about 95 per cent and then just sit down and relax. You then continue to relax for as long as possible, until at last someone notices you are missing and comes looking for you. At which point you can proudly declare that the work is almost finished and you will only need another few minutes and the job will be done and dusted.

So we set to, putting the tools away, returning items to the stores, sweeping the floor, clearing the workbenches. And after an hour or so we had reached Cobbold's cusp of 95 per cent finished. So we settled down to relax and have a chat.

But after a while even that started to pale. So one of us (and afterwards we could never agree whose idea it actually was) came up with a suggestion for a little experiment. One item that hadn't yet been returned to its rightful place in the factory was a steel bar, about 1" square by about 2ft long. We had the bright idea to place the steel bar in the middle of a coil of cable which had power running through it, just to see what happened. That seemed to us at the time to be a really interesting and useful experiment.

So we found a reel of 40/0076 panel wiring cable, almost full with hardly any used, and hooked the ends of the cable into the live and neutral terminals of a 13A plug, and fitted a 13A fuse. We put the coil of cable on edge on the floor, and placed the steel bar in the middle of the cable reel. And then when we were ready, we switched it on.

Immediately, to our surprise and absolute joy, the bar jumped up off the floor and sat, horizontally, in the middle of the cable reel, levitating itself, and vibrating slightly as it did so. And at the same time, a loud hum started emanating from the reel of cable.

We set about congratulated ourselves on our ingenuity, but before long the seriousness of our situation began to dawn on us. The door could open at any time and someone come walking into the room - we'd been there some time and we knew we could expect someone to check up us sooner or later. There would be real trouble for us if we were caught misbehaving with live electricity when we should have been working.

We both knew that switching off the power to our little experiment would be 'interesting', so after a discussion about how to go about it, we took up positions behind the workbenches, and, using a ruler, I poked at the switch on the socket-outlet and switched off the power. To our absolute amazement, the steel bar immediately shot horizontally at high speed across the room, miraculously missing the door by inches, and gouged a large chunk out of the brickwork. We felt sure that had someone entered the room and been standing in the wrong place, it would have chopped his leg off.

Heaving a sigh of relief, we finished clearing up the room with alacrity, Sigi taking the offending piece of metal bar back to the steel racks, whilst I quickly cut off the 13A plug from the reel of cable and returned it to the cable cupboard. I then swept the floor, and removed the shards of brick into the rubbish bin.

After swearing each other to secrecy about our little escapade, we returned suitably chastened to our drawing boards, and attacked our work with vigour for the rest of the afternoon.

Sadly, Sigi died a few years ago, taking, I believe, our little secret to the grave with him. But I feel that since it all happened so many years ago, and the factory where it took place has now become our local Council offices, the story can now be told.

But I always remembered the three important lessons I learnt that day:

  1. Don't fool around;
  2. If you do fool around, then don't get caught;
  3. If you don't get caught, then don't tell anyone about it.

Oh, and I learnt a little bit about electrodynamics that day, too!

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