function Init() {
    //Preload Menu Images
    if (document.images) {
        pic1 = new Image(148, 313);
        pic1.src = "images/main_menu_home.jpg";

        pic2 = new Image(148, 313);
        pic2.src = "images/main_menu_contact.jpg";

        pic3 = new Image(148, 313);
        pic3.src = "images/main_menu_about.jpg";

        pic4 = new Image(148, 313);
        pic4.src = "images/main_menu_history.jpg";

        pic5 = new Image(148, 313);
        pic5.src = "images/main_menu_services.jpg";

        pic6 = new Image(148, 313);
        pic6.src = "images/main_menu_survey.jpg";

        pic7 = new Image(148, 313);
        pic7.src = "images/main_menu_promotions.jpg";

        pic8 = new Image(148, 313);
        pic8.src = "images/page-top.jpg";

    }
}

function nav_home() {
    document.getElementById("NavMenu").src = "images/main_menu_home.jpg";
}

function nav_contact() {
    document.getElementById("NavMenu").src = "images/main_menu_contact.jpg";
}

function nav_about() {
    document.getElementById("NavMenu").src = "images/main_menu_about.jpg";
}

function nav_history() {
    document.getElementById("NavMenu").src = "images/main_menu_history.jpg";
}

function nav_services() {
    document.getElementById("NavMenu").src = "images/main_menu_services.jpg";
}

function nav_survey() {
    document.getElementById("NavMenu").src = "images/main_menu_survey.jpg";
}

function nav_off() {
    document.getElementById("NavMenu").src = "images/main_menu_off.jpg";
}

function nav_promos() {
    document.getElementById("NavMenu").src = "images/main_menu_promotions.jpg";
}

function nav_promos_off() {
    document.getElementById("NavMenu").src = "images/main_menu_off.jpg";
}