Text in the center if little

HTML & CSS
1

I want to have the little text for a div (the div for text of the site) at the center
but the bigger not to have this style.
Till now I use javascript to find the lenght of the characters of the div but I want to know if there is a way with plain css

2

Little text?
Bigger text?

Can you post an example?

3

Sorry for my English.
So little text is the text with little length.
A text with 6-7 lines for example,as you see that in IE.
A bigger for example with 15-20 lines…
This div has height 330px so I want a way the text with 130-150px height to have a distance from the top and the bottom