Why did the water go up in the glass jar ?

 Recently I saw the demonstration of a scientific experiment . Experiment is very

 simple . The illustrator comes in holding a glass jar with a cap on its top . The

 glass jar contains little amount of water .

In the beginning itself , illustrator makes it clear that the pressure on both glass jar

 and on its topmost cap area have maintained same . Now he just holds the glass

 jar in his hand . Suddenly the water which was there in the bottom of glass jar ,

 moves up and was collected in the top most cup area .

Remember he has not put any pressure . Pressure is same on every position . But

 also water moves up. What makes the water to go up ?

It is based on the principle of Charles law which states that if the pressure is kept

 constant , then the volume is directly proportional to temperature .

T1 / T2 = V1/V2 if p is constant.

Where T1,T2 =temperature V1,V2 = volume p= pressure.

Now in this case , as the pressure is constant , the temperature of glass jar is

 lesser compared to human hand temperature . So the air which is present in the

 empty spaces inside the glass jar gets heated up, because of human body

 temperature . Hence it starts expanding .

At this time , it tries to occupy the position which is already water is using . So it

 displaces the water to another position which is the top most cup . 

This is the reason behind the displacement of water inside the glass jar .