Instrumentation - six's thermometers

The Six's thermometers (on south side of pan) is on the lower left.

These thermometers measure the maximum and minimum water temperature during each day.

They are reset by shaking them in a downward motion which resets the mercury columns. Water temperature is an important consideration when determining evaporation rates.

Six's thermometers are always placed under water on the south side of the pan (opposite the still well) and adjacent the surface cup anemometer.