How to read a mercury thermometer to determine body temperature

　　A mercury thermometer is a commonly used tool for measuring body temperature, and its reading method is relatively straightforward. It is important to hold the thermometer properly, locate the scale lines, observe the mercury column, read the value, and pay attention to the unit. The details are as follows:

　　1. Hold the thermometer: Grip the end of the mercury thermometer steadily, ensuring that the thermometer remains stable and your eyes are level with the mercury column inside.

　　2. Locate the scale lines: On the surface of the mercury thermometer, there is a series of fine scale lines that indicate specific temperature values. Typically, the scale range of the thermometer is from 35°C to 42°C, with each small division representing 0.1°C.

　　3. Observe the mercury column: Gently rotate the thermometer to locate the top of the mercury column. The mercury column is a silver, elongated liquid column that moves up and down in response to changes in body temperature.

　　4. Read the value: Once the mercury column has stabilized, observe which scale line it aligns with. The temperature indicated by the aligned scale line is the current body temperature reading. Note that you should read the scale line closest to the top of the mercury column.

　　5. Pay attention to the unit: Thermometer readings are typically expressed in degrees Celsius. If necessary, the reading can be converted to another unit, such as Fahrenheit, using the appropriate conversion formula.

　　Before using a mercury thermometer, ensure that the mercury column has been shaken down to below 35°C to ensure measurement accuracy. Additionally, avoid direct contact with the mercury column with your hands when reading the temperature, as the temperature of your hand may affect the reading.