onClick="MyDiv.doScroll('scrollbarPageDown')"

Simulates a click on a scroll-bar component.
Syntax

object.doScroll( [sScrollAction])

Parameters
sScrollAction   Optional. String that specifies how the object scrolls, using one of the following values:             
        scrollbarDown   Default. Down scroll arrow is at the specified location.       
        scrollbarHThumb Horizontal scroll thumb or box is at the specified location.   
        scrollbarLeft   Left scroll arrow is at the specified location.
        scrollbarPageDown       Page-down scroll bar shaft is at the specified location.       
        scrollbarPageLeft       Page-left scroll bar shaft is at the specified location.       
        scrollbarPageRight      Page-right scroll bar shaft is at the specified location.      
        scrollbarPageUp Page-up scroll bar shaft is at the specified location. 
        scrollbarRight  Right scroll arrow is at the specified location.       
        scrollbarUp     Up scroll arrow is at the specified location.  
        scrollbarVThumb Vertical scroll thumb or box is at the specified location.     
        down    Composite reference to scrollbarDown.  
        left    Composite reference to scrollbarLeft.  
        pageDown        Composite reference to scrollbarPageDown.      
        pageLeft        Composite reference to scrollbarPageLeft.      
        pageRight       Composite reference to scrollbarPageRight.     
        pageUp  Composite reference to scrollbarPageUp.
        right   Composite reference to scrollbarRight. 
        up      Composite reference to scrollbarUp.    

Scroll a Panel…

<script language="javascript">
function ScrollPanel()
  {
      document.all.Panel1.doScroll('scrollbarPageDown')
  }
</script>