priced as a pair.....one is in Farenheit and the other in Celcius
not intended for human medical applications!
This feature works on the principle of a constricted capillary; on heating, the expansion of the mercury within the bulb forces the mercury column through the constriction.
The constriction prevents the mercury column from retreating under the influence of gravity or mild vibration.
Retraction of the column is accomplished by shaking the thermometer, much like one would a fever thermometer, thus generating centrifugal force and forcing the mercury column back through the constriction.
Do not be concerned about the apparent separation of the mercury column below the constriction. This is a normal condition while the indication is above ambient temperature, and will not affect the accuracy of the indication.
The mercury will rejoin after shaking down to ambient temperature.
IMPORTANT: The thermometer should be reset prior to each use as described above. Be sure to continue shaking until the column registers approximately ambient room temperature.
Place the thermometer into the environment you wish to measure. The thermometer should be allowed to remain exposed to the temperature you wish to measure for at least five minutes,
and ALLOWED TO COOL TO AMBIENT TEMPERATURE BEFORE IT IS READ. READ IN AN UPRIGHT POSITION AND ONLY AFTER IT HAS COOLED TO AMBIENT TEMPERATURE OR YOU WILL OBTAIN A FALSELY HIGH READING.