function makemap() {
var map = new GMap(document.getElementById("map"));
map.addControl(new GLargeMapControl());
map.centerAndZoom(new GPoint(141.358430, 43.060492), 0);
var marker = new GMarker(new GPoint(141.358430, 43.060492));

map.addOverlay(marker);

var WINDOW_HTML = '<div style="width: 240px;"><em>株式会社カメラのいわもと</em><br />札幌市中央区南1条東2丁目<br />マツヒロビル1F</div>';
GEvent.addListener(marker, 'click', function() {
    marker.openInfoWindowHtml(WINDOW_HTML);
  });
marker.openInfoWindowHtml(WINDOW_HTML);
}