42 Common Science 



you cry, the tears roll from your eyeballs and eyelids 

 like water from a duck's back. Your mouth is too dry 

 to talk ; all the saliva rolls down your throat, leaving 

 your tongue and cheeks as dry as cornstarch. 



I think you would soon turn on the adhesion switch 

 again. 



Experiment 15. Touch the surface of a glass of water, 

 and then raise your finger slightly. Notice whether the 

 water tends to follow or to keep away from your finger as 

 you raise it. Now dip your whole finger into the water and 

 draw it out. Notice how the water clings, and watch the 

 drops form and fall off. Notice the film of water that stays 

 on, wetting your finger, after all dropping stops. 



Which do you think is the stronger, the pull of 

 gravity which makes some of the water drip off, or the 



FIG. 21. As the finger is raised the water is drawn up after it. 



