quality:corruption, structural:reformatting
Thermometers

Thermometers containing mercury were invented in the early 18th century by Daniel Gabriel Fahrenheit, though earlier attempts at making temperature-measuring instruments filled with quicksilver had been described in the 1650s. Fahrenheit's mercury thermometer was based on an earlier design that used alcohol rather than mercury; the mercury thermometer was significantly more accurate than those using alcohol. From the early 21st century onwards, the use of mercury thermometers has been declining, and mercury-containing instruments have been banned in many jurisdictions following the 1998 Protocol on Heavy Metals. Modern alternatives to mercury thermometers include resistance thermometers, thermocouples, and thermistor sensors that output to a digital display.