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) {
		Homebutton_over = newImage("images/Homebutton-over.gif");
		Servicesbutton_over = newImage("images/Servicesbutton-over.gif");
		Visionbutton_over = newImage("images/Visionbutton-over.gif");
		EyeConbutton_over = newImage("images/EyeConbutton-over.gif");
		VisionSimbutton_over = newImage("images/VisionSimbutton-over.gif");
		Eyeglassesbutton_over = newImage("images/Eyeglassesbutton-over.gif");
		Patientbutton_over = newImage("images/Patientbutton-over.gif");
		Contactbutton_over = newImage("images/Contactbutton-over.gif");
		preloadFlag = true;
	}
}