// JavaScript Document

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) {
	  
	homepage = new Image();
	homepage.src = "../images/nav_home_over.jpg";
	
	students = new Image();
	students.src = "../images/nav_students_over.jpg";
	
	teachers = new Image();
	teachers.src = "../images/nav_teachers_over.jpg";
	
    preloadFlag = true;
  }
}