var xPos = 100;
var yPos = 100; 
var step = 1;
var delay = 30; 
var height = 0;
var Hoffset = 0;
var Woffset = 0;
var yon = 0;
var xon = 0;
var pause = true;
var interval;
float_div2.style.top = yPos;
function changePos() 
{
width = document.body.clientWidth;
height = document.body.clientHeight;
Hoffset = float_div2.offsetHeight;
Woffset = float_div2.offsetWidth;
float_div2.style.left = xPos + document.body.scrollLeft;
float_div2.style.top = yPos + document.body.scrollTop;
if (yon) 
	{yPos = yPos + step;}
else 
	{yPos = yPos - step;}
if (yPos < 0) 
	{yon = 1;yPos = 0;}
if (yPos >= (height - Hoffset)) 
	{yon = 0;yPos = (height - Hoffset);}
if (xon) 
	{xPos = xPos + step;}
else 
	{xPos = xPos - step;}
if (xPos < 0) 
	{xon = 1;xPos = 0;}
if (xPos >= (width - Woffset)) 
	{xon = 0;xPos = (width - Woffset);   }
}

function start()
 {
 	float_div2.visibility = "visible";
	interval = setInterval('changePos()', delay);
}
function pause_resume() 
{
	if(pause) 
	{
		clearInterval(interval);
		pause = false;
	}
	else 
	{
		interval = setInterval('changePos()',delay);
		pause = true; 
	}
}
start();