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) {
		Explorations_over = newImage("images/Explorations-over.jpg");
		Gallery_over = newImage("images/Gallery-over.jpg");
		Technology_over = newImage("images/Technology-over.jpg");
		History_over = newImage("images/History-over.jpg");
		Library_over = newImage("images/Library-over.jpg");
		Education_over = newImage("images/Education-over.jpg");
		For_Fun_over = newImage("images/For-Fun-over.jpg");
		preloadFlag = true;
	}
}
var preloadFlag = true;