Sailing Glossary - Term Sea water thermometer

A thermometer designed for use in measuring the temperature of sea water. One form consists of a mercury-in-glass thermometer protected by a perforated metal case. Another form consists of a mercury-in-glass thermometer surrounded by a metal case which forms a well around the bulb of the thermometer. When the thermometer is raised from the water, a sample is retained in the well. See bucket thermometer, reversing thermometer.