168 NATURE-STUDY LESSONS. 



(b) Place a finger of one hand in A and a finger 



of the other hand in C. Continue to hold 

 them there for a minute, then withdraw and 

 thrust them into B. How does the water 

 in B now feel to the finger taken from A ? 

 To that taken from C ? 



(c) Compare the temperatures of the finger imme- 



diately before and immediately after being 

 placed in A. 



{d) Compare similarly the temperatures of the 

 finger placed in C. 



{e) Compare the temperatures of the fingers 

 immediately before being placed in B. 



(/") What caused the difference in the sensations 

 in the two fingers when placed in B ? 



{g) Is the water in B hot or cold ? 

 13. Make other observations, as : — 



{a) Determine, by touch, the comparative temper- 

 atures of different articles subjected to the 

 same temperatures for some time; e.g.,\he 

 iron head of a hammer and its wooden 

 handle, the slate and its frame, an iron 

 inkstand and a lead pencil beside it, a piece 

 of oilcloth and a piece of carpet on the same 

 floor — each of the above pairs of articles 

 when lying in the heat of the sun in summer. 



(b) Infer whether touch is an accurate test of the 



temperature of a body. 



C. The Thermometer is Used in the Accurate Determina- 

 tion of Temperature. 



Since the thermometer with Fahrenheit markings is 



more generally used for domestic purposes, it is more 



appropriate for use in these experiments. In a lesson 



