var base = "/pics/";
        if (document.images) {           
            
	img1on = new Image();   img1on.src = base + "ccmapup.gif";
	img12on = new Image();   img12on.src = base + "ccmapmid.gif";
	img13on = new Image();   img13on.src = base + "ccmaplow.gif";
 img1off = new Image();  img1off.src = base + "ccmap_grey.gif";
        }
    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");        
            }
}
    function imgOn2(imgName) {
            if (document.images) {
                document[imgName].src = eval(imgName + "2on.src");        
            }
}
    function imgOn3(imgName) {
            if (document.images) {
                document[imgName].src = eval(imgName + "3on.src");        
            }
}