Nansen bottle

The Nansen bottle or Kippthermometer is a hydrographic unit for taking water samples from specific depths. Moreover, it has receptacles for special mercury thermometer with which the temperature of the heat and sea, the hydrostatic pressure at the desired depth can be measured. It was designed in 1910 by the oceanographers Fridtjof Nansen.

The " bottle " is a cylinder made of metal or plastic. The two tapered ends of this cylinder can be closed with one lid. He is attached to the top and bottom on a leash and let down into the sea. When the desired depth is reached, you can at the dew drop weight, called "Messenger", slide down, the release mechanism on a cylinder snaps off the top when hitting and he then turns 180 °. During this rotation, the two valves that are located up and down, tightly closed. Thus, the water sample is included and can be undisturbed brought to the surface. With a small tap, the water can then be removed.

Using a mercury - Kippthermometers the temperature of the water is measured in the sampling depth at the same time. In order for the measurement to catch up is not distorted, the thermometer has a weak spot, at the break if tipped over the Nansen bottle of mercury thread and so ensures that the mercury in the reservoir is separated from the mercury in the column. Thus the length of the column is fixed and the in situ temperature can be read by the retrieving. As the water pressure would be influenced by the compression of the capillary tube temperature measurement, the thermometer is protected by a pressure-resistant housing. At the same time an unprotected thermometer is carried and tilted; the subsequent comparison of the two measurements allows us to determine the temperature as well the pressure.

Often is also triggered by the tilting mechanism further messenger weight, further slides on the canvas down and encounters a greater depth into Inappropriate more Nansen bottle and its mechanism is triggered. By one above the other orders a series of bottles and weights on a leash and lets in depth, can in a very short time a number of samples and temperature / pressure measurements within an entire water column win.

The Nansen bottle was in practice largely replaced by the patented in 1966 by Shale Niskin Niskinflasche that is attached to a CTD rosette, since the handling by the single fastening rope is quite time consuming.

Footnotes

• Oceanography
• Oceanography
• Fridtjof Nansen
• Gauge