1894

Nansen bottle

• Fridtjof Nansen had to wonder
• whether the seawater was layered—
• how temperature and salinity varied
• with depth. He had to wonder
• and to figure how to get the data.
• The famous explorer and statesman
• Fridtjof Nansen combined a reversing
• thermometer with a bottle, both being triggered
• by a “messenger weight” to capture
• temperature and a water sample at a given depth.

Niskin improvements

• The Niskin bottle doesn’t need to be rotated to trap a water sample,
• and is made of plastic to reduce contaminating its sample.
• Some Niskin bottles are preset to close at a given depth
• and some are triggered by an electric signal from the surface.
• Many Niskin bottles may be mounted on a rosette
• to capture temperatures and samples at many depths.

Not obvious

• You had to wonder
• and the point is
• people didn’t,
• which is why one
• rarely needs to prove
• it isn’t obvious.