nav1on = new Image(); 
nav1on.src = "site_images/nav1_on.gif";
nav1off = new Image(); 
nav1off.src = "site_images/nav1_off.gif";

nav2on = new Image(); 
nav2on.src = "site_images/nav2_on.gif";
nav2off = new Image(); 
nav2off.src = "site_images/nav2_off.gif";

nav3on = new Image(); 
nav3on.src = "site_images/nav3_on.gif";
nav3off = new Image(); 
nav3off.src = "site_images/nav3_off.gif";

nav4on = new Image(); 
nav4on.src = "site_images/nav4_on.gif";
nav4off = new Image(); 
nav4off.src = "site_images/nav4_off.gif";

nav5on = new Image(); 
nav5on.src = "site_images/nav5_on.gif";
nav5off = new Image(); 
nav5off.src = "site_images/nav5_off.gif";

nav6on = new Image(); 
nav6on.src = "site_images/nav6_on.gif";
nav6off = new Image(); 
nav6off.src = "site_images/nav6_off.gif";

nav7on = new Image(); 
nav7on.src = "site_images/nav7_on.gif";
nav7off = new Image(); 
nav7off.src = "site_images/nav7_off.gif";

nav8on = new Image(); 
nav8on.src = "site_images/nav8_on.gif";
nav8off = new Image(); 
nav8off.src = "site_images/nav8_off.gif";