A dual-scale Thermometer chart

This goes in the documents header:

<script src="RGraph.common.core.js"></script>
<script src="RGraph.drawing.yaxis.js"></script>
<script src="RGraph.bar.js"></script>

Put this where you want the chart to show up:

<canvas id="cvs" width="100" height="400">
    [No canvas support]
</canvas>

This is the code that generates the chart: