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Magnifying glass for reversing thermometer
Magnifying glass for reversing thermometer

Magnifying glass for reversing thermometer

Date1980s
Object number00055788
NameThermometer
MediumMetal, glass, string
DimensionsOverall (not extended): 39 mm, 77 g, 33 mm
Copyright© CSIRO
ClassificationsTools and equipment
Credit LineAustralian National Maritime Museum Collection Gift of CSIRO
DescriptionMetal magnifying glass for reading reversing thermometer with a string attached to the side.HistoryAlso referred to as a loupe, the magnifying glass assists in reading the temperature on reversing thermometers attached to a water sampler deployed off a vessel. Reversing thermometers can have a protective outer glass casing or come without, with temperature readings being visible to the 10th of a degree Fahrenheit. However, with the small labelling and glass elements, the magnifying glass is of great assistance when working out at sea under less than desirable conditions. They are similar to their counterparts used in the jewellery industry but are made more robust for seafaring conditions.SignificanceThe magnifying glass brings attention to the reality of the meticulous work that needs to be conducted whilst aboard a research vessel, usually experiencing arduous conditions in open seas. The process of retrieving water samples and measurements began as an elaborate system of many manual moving parts and instruments. This system includes securing reversing thermometers to water samplers to be deployed, and the clever configuration of lines and weight triggers that capture samples at designated depths. The magnifying glass would be put to good use once the deployed samplers are hauled back on board. Scientists and assistants would use the magnifying glass to read the temperatures to a 10th of a degree Fahrenheit that were locked into the thermometers while still at depth underwater.