anchor.diff:          position: location.position,
           label: location.label,
           title: location.tooltip,
  +        <% if !marker_cluster %>
  +        map: map,
  +        <% end %>
         });
         if (location.popupHtml) {
           var infoWindow = new google.maps.InfoWindow({
  
positive.code:       return marker;
      });
      
      new MarkerClusterer(
        map,
        markers,
        {
          imagePath: "https://developers.google.com/maps/documentation/javascript/examples/markerclusterer/m"
        }
      );
    }
  </script>
  
negative.code:     # https://developers.google.com/maps/documentation/javascript/tutorial#zoom-levels
      zoom = 10
    end
  end
  if !defined?(marker_cluster)
    marker_cluster = false
  end
  Rails.logger.debug{"map/display latitude: #{defined?(latitude)}, #{latitude.inspect}"}
  if !defined?(latitude) || latitude.nil?
  