title: Why can't I drill down from column to bar?
body: <p>Highcharts has a lovely demo of a chart that <a href="http://jsfiddle.net/gh/get/jquery/1.7.2/highslide-software/highcharts.com/tree/master/samples/highcharts/drilldown/across-types/" rel="nofollow">drills down from columns to pies</a>. But if I try to switch things up so it uses bars instead of pies, I get <a href="http://jsfiddle.net/amandabee/SeY63/1/" rel="nofollow">bars and then bars</a>, not columns and then bars:</p>
  
  <pre><code>$(function () {
  
  // Create the chart
  $('#container').highcharts({
      chart: {
          type: 'bar' //change this to "pie" and it works just fine. 
      },
      series: [{
          name: 'Things',
          data: [{
              name: 'Animals',
              y: 5,
              drilldown: 'animals'
          }, {
              name: 'Fruits',
              y: 2,
              drilldown: 'fruits'
          }, {
              name: 'Cars',
              y: 4,
              drilldown: 'cars'
          }],
          type: 'column'
      }],
      drilldown: {
          series: [{
              id: 'animals',
              data: [
                  ['Cats', 4],
                  ['Dogs', 2],
                  ['Cows', 1],
                  ['Sheep', 2],
                  ['Pigs', 1]
              ]
          }, {
              id: 'fruits',
              data: [
                  ['Apples', 4],
                  ['Oranges', 2]
              ]
          }, {
              id: 'cars',
              data: [
                  ['Toyota', 4],
                  ['Opel', 2],
                  ['Volkswagen', 2]
              ]
          }]
      }
  }) });
  </code></pre>
  
  <p>Is it possible to switch from columns to bars when I drill down?</p>