function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		index_08_over = newImage("images/index_08_over.gif");
		index_08_down = newImage("images/index_08_down.gif");
		index_09_over = newImage("images/index_09_over.gif");
		index_09_down = newImage("images/index_09_down.gif");
		index_10_over = newImage("images/index_10_over.gif");
		index_10_down = newImage("images/index_10_down.gif");
		index_11_over = newImage("images/index_11_over.gif");
		index_11_down = newImage("images/index_11_down.gif");
		index_12_over = newImage("images/index_12_over.gif");
		index_12_down = newImage("images/index_12_down.gif");
		index_13_over = newImage("images/index_13_over.gif");
		index_13_down = newImage("images/index_13_down.gif");
		preloadFlag = true;
	}
}