Water sampler
Water sampler, 013
During the First Fram Expedition, Fridtjof Nansen and his crew measured the temperature in the ocean around the North Pole all the way down to 3 800 metres. They also found the salinity of the sea water at different depths. To do this they needed water samples. A water sample from a given depth can also tell us about algae and other sorts of life in the sea.
Fridtjof Nansen was a pioneer in polar research and oceanography and carried out some extraordinary scientific measurements during his drift with the Fram in the years 1893-96. He is the one that developed and devised one of the first functional water samplers in the world, the so-called Nansen bottle.
A water sampler is a device that you use for collecting water in the sea, in a lake or from a river.
Usually this instrument is a cylinder with the capacity of containing 1 to 10 litres of water.
The standard Nansen bottle was made of metal and had a capacity of 1, 25 litres. You lowered it in the water to the desired sampling depth from the surface, and then you closed it by using a little weight that you let fall on the winch wire affixed to it. The weight slided down the cable and the water sampler then turned around, closed itself and isolated your amount of water from the water on the outside.
Today waters samplers are normally mounted together in a rosette, lowered and triggered off to close by electrical signals through the wire. Often you will find a thermometer fixed to it.