function initialize() {
  if (GBrowserIsCompatible()) {
    var map = new GMap2(document.getElementById("map_canvas"));
    map.setCenter(new GLatLng(51.877829,-0.411483), 12);
        
    map.addOverlay(new GMarker(new GLatLng(51.877829,-0.411483)));
    map.setUIToDefault();

  }
}
window.onload = initialize