How to correctly use mercury thermometer

Mercury thermometer is we are familiar with, we first contact with the body of thermometer is the mercury thermometer, mercury thermometer is a kind of expansion type thermometer, used to measure the 0-150 ℃ or 500 ℃ within the range of temperature, has the function of high precision. It can only serve as on-site monitoring instrument. Use it to measure temperature, not only is simple and intuitive, but also can avoid external remote transmission error of the thermometer. Using mercury temperature time should pay attention to the following points: ( 1) Should be check before use. More than standard liquid temperature comparison method may be used for checking or more advanced precision thermometer calibration. （ 2) Not allowed to use the temperature more than the thermometer of the measured value of the largest scale value. （ 3) Thermometer have thermal inertia, after should reach a steady state in thermometer readings. Reading should be in the highest temperature on convex curved surface tangent to read, looking directly at them. （ 4) Mercury thermometer should be measured working medium with vertical or inclined shaped the direction of flow. （ 5) Fracture of mercury mercury thermometer often happen, eliminating methods are: (1) cold repair method: put thermometer temperature bag into the dry ice and alcohol mixture ( Temperature shall not exceed - 38℃） Cold, all make the mercury in the capillary contraction at the temperature measurement in the package. (2) hot fix method: insert the thermometer slow temperature slightly higher than the upper limit of constant temperature trough, the broken part the mercury and the mercury column, and then slowly remove the thermometer and cooling to room temperature in the air. The above is the mercury thermometer in the items need to be aware of when using, the use of hope for your help!