// Ë«»÷¹öÆÁЧ¹û
var lastTop;
var timer;
document.ondblclick=startScroll;
document.onmousedown=stopScroll;
function startScroll()
{
	timer=setInterval("scrolling()",50);
}
function scrolling()
{
	lastTop=document.body.scrollTop;
	window.scroll(0,++lastTop);
	if(lastTop!=document.body.scrollTop)
		stopScroll();
}
function stopScroll()
{
	clearInterval(timer);
}