title: jQuery Page Scroll every time Down when Key press Down in single page
body: <p>I Want page scroll down every time when i press key down from key board i want page scroll down to next something pixcel fixed each time </p>
  
  <p>anyone please help me how to do it</p>
  
  <p>I Want Continue Scroll on every key press at the last div</p>
  
  <pre>http://jsfiddle.net/dhaval17/etfYz/</pre>