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) {
		bio_over = newImage("/include/images/nav/images/bio-over.jpg");
		artwork_over = newImage("/include/images/nav/images/artwork-over.jpg");
		collections_over = newImage("/include/images/nav/images/collections-over.jpg");
		exhibitions_over = newImage("/include/images/nav/images/exhibitions-over.jpg");
		awards_over = newImage("/include/images/nav/images/awards-over.jpg");
		agents_over = newImage("/include/images/nav/images/agents-over.jpg");
		preloadFlag = true;
	}
}