var imageRoot = '/images/';
var preloadFlag = false;

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 = imageRoot + changeImages.arguments[i+1];
		}
	}
}

function preloadImages() {
	if (document.images) {
		michel_o = newImage(imageRoot + "bt_michel_o.gif");
		talbot_o = newImage(imageRoot + "bt_talbot_o.gif");
		sheehy_o = newImage(imageRoot + "bt_sheehy_o.gif");
		monteiro_o = newImage(imageRoot + "bt_monteiro_o.gif");
		ronayne_o = newImage(imageRoot + "bt_ronayne_o.gif");

		preloadFlag = true;
	}
}