Figure 14. Negretti and Zambra thermometers, older models. These were reversing thermometers completely protected by an outer glass casing. This type of thermometer was manufactured from 1878 until 1912. The scales were graduate d in degrees and half-degree centigrade. Length of these thermometers was about 24 cm, diameter of reservoir about 1.1 cm, and diameter of tube about 1.3 cm.
Photo Category: Oceanography - Historical instruments