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Kathy Sykes' Diary

Day 6: Accurate Weighing Balance

Astonishing first day! Began with a helicopter ride up and over Franz Josef Glacier. Was awake most of the night - too excited to sleep, at the prospect of this flight (small child!). Had been hoping hard that the weather would hold.

Photo: snowBrilliant blue sky - and a 'copter ride to die for. We swooped over smooth desert - like snow-fields; craggy folded, madly-blue ice sculptures; over deep fissures - of intense blue, over snowy, jagged tips of mountains and over the whole Frank Josef Valley. The finale was swooping over a valley choked up in cloud skirting just above cloud level, in pointed bits of tree-top sticking out of the cloud. Woosh! Just amazing. I just love helicopters. Had tears in my eyes over the snow fields. Just excruciatingly pretty.

Photo: the sawmillAnd finally - we get "dumped" at the sawmill - our 'home' for the next 6 weeks. Surrounded by snow-capped mountains, with some more gentle hills nearby. We are so, so lucky!

So - our challenges. Pretty nervous - just how hard are they going to be?! Jonathan - a metal detector!? Now that's hard! Me and Mike L - an accurate balance, to weigh the kilos of gold Mike B and Ellen are going to collect.

A weighing balance it seems very straightforward. Mike L seemed a little disgusted - it's just too easy, and not dramatic enough. He thought we'd be able to do it in a day.

Photo: Kathy and MikeBUT - making one that can weigh the amounts of gold M + E can get - I think is pretty hard. Mike B thinks they're going to get 5 - 20g. I can't believe that. I'd be thrilled to bits - but there's NO WAY. So - We decided we needed to make a balance that could measure 5 - 20g - but could also weigh things of past 10 - 100 mg.

We messed about with a metal rod - a balance arm. It worked fine for 20g kinds of weights - but wasn't so hot for ½ kg. And it needed to work for ½ kg - since that's the only weight we actually have that we know is a particular weight. It's a 500g bag of sugar. And if we can't weigh that accurately none of our weights will be accurate.

Photo: Kathy with scalesMike knocked up another balance using a razor blade as a pivot, but it still wasn't any good for 500g. Then we talked about using a length of tube - fill it with sugar and the height would relate to the mass of sugar. I was a bit less excited about this - the sugar probably packs differently when wet and the amount you push it down the tube will affect the height. BUT - if we could start with sugar - then say compare it with water - that might work. And water has a density we know - 1 gram per cubic centimetre. (If only we had some known volumes - eg, if 5 cm3 - we could just do it all based on water. Sigh!

Anyway - I had a very cold, sad end-of-day. I counted the number of nails in a big bag that balanced against the sugar (12,081) and went off thinking we must be able to do better than sugar tubes.

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Photo: Kathy Sykes
Metal Detector Interactive