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2.1.4 Experiment： measure water temperature by using 
a thermometer 
The following two tips should be followed before we use a thermometer. 
1.Notice its scale range—the temperature range a thermometer can measure.If the temperature is estimated beyond the highest or the lowest temperature it can measure， change for a proper one.Otherwise， the liquid in the thermometer may swell out and destroy the thermometer or the value fails to be read on the thermometer. 
2. Make sure of its division value so as to read the temperature accurately in measurement. 
In using a thermometer to measure the temperature of a liquid， the correct method is as follows. 
The glass bulb of a thermometer should be immersed completely into the liquid which is to be measured.It cannot touch the bottom or the surroundings of a container（Fig 2—2）. 
Wait a moment after the glass bulb of the thermometer is immersed into the liquid.Wait until the reading on the thermometer becomes stable. 
When you read the value， the glass bulh should remain to be in the liquid.Your sight and the upper surface of the liquid column should be at the same level （Fig.2—3 ） . 
（ Purpose） Learn to use a thermometer and estimate the temperature. 
（Apparatus） One thermometer， hot water in a thermos， one cup. 
（ Procedures ） 
（1） Pour a cup of hot water and measure its temperature with the thermometer. 
（2） Cool off the water to the degree that your fingers can be put into it but still feel very hot.Measure its temperature first by estimation and then with the thermometer. Fill in the following table with each estimated and actual temperature each time including this time.