How can I increase the sampling rate for AnalogRead() on Arduino Uno?

[cnh1995]

I connected the A0 pin of arduino uno to +5V and read the voltage using analogRead () and displayed the result and elapsed time on the serial monitor. Its reading only 30 samples per second. What's going wrong? How do I change the clock prescaler for the ADC?

 

[Hesch]

How do I change the clock prescaler for the ADC?

See page 264: http://www.atmel.com/Images/doc8161.pdf

The ADC is integrated in the processor, I assume.