if (document.images) {         
            img1on = new Image();      
            img1on.src = "i/img1_on.jpg";
            
            img2on = new Image();      
            img2on.src = "i/img2_on.jpg";
            
            img3on = new Image();      
            img3on.src = "i/img3_on.jpg";
            
            img4on = new Image();      
            img4on.src = "i/img4_on.jpg";
            
            img5on = new Image();      
            img5on.src = "i/img5_on.jpg";
            
            img6on = new Image();      
            img6on.src = "i/img6_on.jpg";
            
            img7on = new Image();      
            img7on.src = "i/t_img1_on.jpg";
            
            img8on = new Image();      
            img8on.src = "i/t_img1_on.jpg";
            
            img10on = new Image();      
            img10on.src = "i/t_img1_on.jpg"
            
            img11on = new Image();      
            img11on.src = "i/t_img1_on.jpg"
            
            img12on = new Image();      
            img12on.src = "i/t_img1_on.jpg"
            
            img13on = new Image();      
            img13on.src = "i/t_img13_on.jpg"
            
            img1off = new Image(); 
            img1off.src = "i/img1_off.jpg"; 
            
            img2off = new Image(); 
            img2off.src = "i/img2_off.jpg"; 
            
            img3off = new Image(); 
            img3off.src = "i/img3_off.jpg"; 
            
            img4off = new Image(); 
            img4off.src = "i/img4_off.jpg"; 
            
            img5off = new Image(); 
            img5off.src = "i/img5_off.jpg";
                        
            img6off = new Image(); 
            img6off.src = "i/img6_off.jpg";  
            
            img7off = new Image(); 
            img7off.src = "i/t_img1_off.jpg";
            
            img8off = new Image(); 
            img8off.src = "i/t_img1_off.jpg";
            
            img10off = new Image(); 
            img10off.src = "i/t_img1_off.jpg";
            
            img11off = new Image(); 
            img11off.src = "i/t_img1_off.jpg";
            
            img12off = new Image(); 
            img12off.src = "i/t_img1_off.jpg";
            
            img13off = new Image(); 
            img13off.src = "i/t_img13_off.jpg";
}


function imgOn(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "on.src");
        }
}


function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");
        }
}