reversing thermometer

instrument
verifiedCite
While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions.
Select Citation Style
Feedback
Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login).
Thank you for your feedback

Our editors will review what you’ve submitted and determine whether to revise the article.

External Websites
Related Topics:
thermometer

reversing thermometer, oceanographic device for measuring underwater temperature and pressure. It consists of two mercury thermometers—one protected from the water pressure and the other exposed—mounted so that they can slide up and down a cable lowered from a ship. When the reversing thermometers have been lowered to the depth to be measured, a device called a messenger is dropped down the cable, causing the thermometers to be inverted, breaking their mercury columns, and preserving their temperature readings as the device is hauled back on board ship. The exposed and protected thermometers will show different temperatures; the variation is systematically related to water pressure. From the exposed thermometer, the underwater temperature is obtained, while from the difference in the two readings, the water pressure is calculated or read from tables.

This article was most recently revised and updated by John P. Rafferty.