OverviewA thermometer is a useful aid used to measure body temperature. A thermometer is usually filled with mercury. Mercury in the tube rises when expanded by an increase in body temperature.
Update Date 1/10/2016
Updated by: Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.