Ramya and I went over to the flea market in Burkliplatz yesterday. The market is heaven for anyone with the slightest interest in antiques, art, or old machines. You find all sorts of people giving away/selling all sorts of interesting things. I've seen matchlocks, snow axes, gas masks, French and English army helmets, accordions, sextants, and several other things you can't imagine buying at the local supermarket.
One of the things we bought yesterday was an aneroid barometer, our second (the long one with the thermometer above it). This one has a hand-carved wood base, is about 60 years old, and was made in Zurich by an optician named Schulthess (couldn't Google them, no idea if they exist any more). It has a thermometer on it as well. When I was looking at it, the kindly old gentleman at the shop asked me if I understood any Swiss dialects. When I said I barely understand the language proper, he proceeded to explain to me that
thermometers which have a tiny spiral vial containing the mercury at the bottom have a name in Swiitzerduutsch which means something like "the rear end of a pig", possibly because to some, it looks like the curled tail of a pig.The other barometer we bought a few months ago is just a barometer, is about 70 years old, and was made by an optician in Frankfurt.
It serves as a better example for demonstrating how an aneroid barometer works. See the corrugated circle somewhere near the centre, on the inside? That's an evacuated container. It has a spring on the inside that prevents atmospheric pressure from causing it to collapse. However, the spring gets extended or compressed based on how much pressure the atmosphere exerts on the evacuated container (needless to say, this is a very sensitive spring). The movement of the spring is translated by a system of cogs to movement of an arm over a dial. This arm is the blue arm in the "Frankfurt barometer", indicating atmospheric pressure on one side, and its effect on the weather on the other side. "Veränderlich", "schön" and "trocken" respectively mean "changeable", "beautiful", and "dry" in German. There's another arm that can be manually moved, which is useful for marking measurements and observing relative changes to a certain reading.
