Abstract: A thermometer is disclosed comprising a housing with a lens member and a sensing sleeve extending from the lens member. The lens member is configured to define an enclosed chamber in which a temperature indicating means is disposed. The temperature indicating means is attached to a shaft which extends into the sensing sleeve. A temperature responsive element is mounted within the sleeve and operatively associated with the shaft to rotate shaft and indicating means in response to changes in temperature. Means for constraining mechanically induced rotation of the shaft and indicator means to a predetermined arc of angular displacement are provided. In an important aspect of the invention, the constraining means permit temperature induced rotation of the shaft and the indicator means to exceed the pre-determined arc of angular displacement. The constraining means utilized include fusible stop arrangements and the introduction of a dampening fluid to the enclosed chamber of the thermometer housing.