function TextualZoomControl() {
    }
    TextualZoomControl.prototype = new GControl();
 
    // Creates a one DIV for each of the buttons and places them in a container
    // DIV which is returned as our control element. We add the control to
    // to the map container and return the element for the map class to
    // position properly.
    TextualZoomControl.prototype.initialize = function(map) {
      var container = document.createElement("div");
 
      var zoomInDiv = document.createElement("div");
      this.setButtonStyle_(zoomInDiv);
      container.appendChild(zoomInDiv);
      zoomInDiv.appendChild(document.createTextNode("+"));
      GEvent.addDomListener(zoomInDiv, "click", function() {
        map.zoomIn();
      });
 
      var zoomOutDiv = document.createElement("div");
      this.setButtonStyle_(zoomOutDiv);
      container.appendChild(zoomOutDiv);
      zoomOutDiv.appendChild(document.createTextNode("-"));
      GEvent.addDomListener(zoomOutDiv, "click", function() {
        map.zoomOut();
      });
 
      map.getContainer().appendChild(container);
      return container;
    }
 
    // By default, the control will appear in the top left corner of the
    // map with 7 pixels of padding.
    TextualZoomControl.prototype.getDefaultPosition = function() {
      return new GControlPosition(G_ANCHOR_TOP_RIGHT, new GSize(5, 5));
    }
 
    // Sets the proper CSS for the given button element.
    TextualZoomControl.prototype.setButtonStyle_ = function(button) {
      button.style.textDecoration = "none";
      button.style.color = "#0000cc";
      button.style.backgroundColor = "white";
      button.style.font = "small Arial";
      button.style.border = "1px solid black";
      button.style.padding = "2px";
      button.style.marginBottom = "3px";
      button.style.textAlign = "center";
      button.style.width = "1em";
      button.style.cursor = "pointer";
    }