function preload () {
	var image1 = new Image();
    image1.src = "images/icon-a-1-a.png";	
	var image2 = new Image();
    image2.src = "images/icon-a-1-h.png";
	var image3 = new Image();
    image3.src = "images/icon-a-2-a.png";
	var image4 = new Image();
    image4.src = "images/icon-a-2-h.png";
	var image5 = new Image();
    image1.src = "images/icon-a-3-a.png";	
	var image6 = new Image();
    image2.src = "images/icon-a-3-h.png";
	var image7 = new Image();
    image3.src = "images/icon-a-4-a.png";
	var image8 = new Image();
    image4.src = "images/icon-a-4-h.png";
}
if (window.addEventListener)
	window.addEventListener("load", preload, false);
else if (window.attachEvent)
	window.attachEvent("onload", preload);