var delta = 0; 
function zoomMap(inc) {  
 newdelta=delta+inc; 
 
 if(newdelta<0){
  alert("You cannot zoom in any further");  
  return;
 }else if(newdelta>9){
  alert("You cannot zoom out any further");
  return;
 }else{
  delta = newdelta;
 }
  
 document.getElementById('mapimg').src="http://www.multimap.com/clients/gif.cgi?client=hacket&lon="+mylon+"&lat="+mylat+"&height=249&width=249&ds="+delta; 
}
function SetMapDelta(setdelta) { 
 document.getElementById('mapimg').src="http://www.multimap.com/clients/gif.cgi?client=hacket&lon="+mylon+"&lat="+mylat+"&height=249&width=249&ds="+delta; 
}