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) {
        Menu_1_over = newImage("images/navL01TypesOff.jpg");
        Menu_2_over = newImage("images/navL02ClinicalsOff.jpg");
        Menu_3_over = newImage("images/navL03YourAppointmentOff.jpg");
        Menu_4_over = newImage("images/navL04FormsOff.jpg");
        Menu_5_over = newImage("images/navL05DietOff.jpg");
        Menu_6_over = newImage("images/navL06OurDoctorOff.jpg");
        Menu_7_over = newImage("images/navL07MissionOff.jpg");
        Menu_8_over = newImage("images/navL08ScheduleApptOff.jpg");
        
        preloadFlag = true;
    }
}

preloadImages();