function init(){  
  if (navigator.appName == "Netscape") {  
    layerRef="document.layers";  
    styleSwitch="";  
    }else{  
	layerRef="document.all";  
    styleSwitch=".style";  }  
}  
function hideLayer(layerName){  
  eval(layerRef+'["'+layerName+'"]'+styleSwitch+'.visibility="hidden"');  
}  

function showLayer(layerName){  
  eval(layerRef+'["'+layerName+'"]'+styleSwitch+'.visibility="visible"');  
}  
function swapImage(image_src, image_name){  
 if (document.images){
eval('this.document.'+image_name+'.src="'+image_src+'"');
					}
}