Fixed filtering, legend order, minor code changes.

<!DOCTYPE html>
<html lang="en">
<head>
    <title>dc.js multi-line chart</title>

<div class="container">
    <h1>Multi-Line Chart in dc.js</h1>

<div class="row">
        <div id="data-count" class="span12">
            Showing <span class="filter-count"/></span> of <span class="total-count"></span> data points
            | <a href="javascript:dc.filterAll(); dc.renderAll();">Reset All</a>
        </div>
    </div>

<div class="row">
        <div id="time-chart" class="dc-chart span6">
            <strong>Time</strong>
            <small class="text-muted">
            <time id="date-start" datetime="2012-08-26 20:09-0700">8:09pm on August 26th, 2012</time> &ndash;
            <time id="date-end" datetime="2012-08-26 20:09-0700">8:09pm on August 26th, 2012</time>
            </small>
            <a class="reset" href="javascript:time_chart.filterAll(); dc.redrawAll();" style="display: none;">
                reset
            </a>

<div id="temp-chart" class="dc-chart span6">
            <strong>Temperature</strong>
            <a class="reset" href="javascript:temp_chart.filterAll(); dc.redrawAll();" style="display: none;">
                reset
            </a>

</div>

</div>

var dataset = data.map(coerce_row);

// charts
var time_chart = dc.compositeChart("#time-chart"),
    temp_chart = dc.barChart("#temp-chart"),
    width = temp_chart.root()[0][0].parentElement.clientWidth;

// crossfilter
var add = function(p, d){ return p + d.count;},
    rem = function(p, d){ return p - d.count;},
    ini = function(){ return 0;},
    ndx = crossfilter(dataset),
    all = ndx.groupAll().reduce(add, rem, ini),
    fields = ndx.dimension(function(d){ return d.field;}).group(),
    time_field = ndx.dimension(function(d) { return JSON.stringify([d.time, d.field]);}),
    date_acc = function(d){ return new Date(JSON.parse(d.key)[0]);},
    field_acc = function(d){ return JSON.parse(d.key)[1];},
    time_fields = time_field.group().reduce(add, rem, ini),
    temperature = ndx.dimension(function(d){return d.temperature;}),
    temperatures = temperature.group().reduce(add, rem, ini);
    extent = d3.extent(dataset, function(d){return d.time;}),
    date_format = d3.time.format("%b %d %I:%M %p");

d3.select("#date-start")
    .attr("datetime", extent[0])
    .text(date_format(extent[0]));
d3.select("#date-end")
    .attr("datetime", extent[1])
    .text(date_format(extent[1]));

dc.dataCount("#data-count")
// Since the number of records (returned by .size()) isn't the same as the number
// of data points we're aggregating, supply a size-like object that returns the
// total number of data points represented.
    .dimension({size: function(){return dataset.reduce(add, 0);}})
    .group(all);

time_chart
    .width(.5 * width)
    .height(400)
    .dimension(time_field)
    .elasticY(true)
    .elasticX(true)
    .xAxisLabel("Observation Time")
    .yAxisLabel("Count")
    .x(d3.time.scale().domain(extent))
    .renderHorizontalGridLines(true)
    .renderVerticalGridLines(true)
    .legend(dc.legend().x(0.35*width).y(260).itemHeight(13).gap(5))
    .brushOn(false)
    .compose(fields.all().map(function(d, fi){
        var field = d.key;
        return dc.lineChart(time_chart)
            .group({
                all: function(){
                    return time_fields.all().filter(function(d){ return field_acc(d) == field;});
                }
            }, field)
            .colors(['#1f77b4', '#ff7f0e', '#2ca02c','#d62728'])
            .colorAccessor(function(){return fi;})
            .keyAccessor(date_acc);
    }));

temp_chart
    .width(.5 * width)
    .dimension(temperature)
    .x(d3.scale.linear().domain([0, 100]))
    .xAxisLabel("Temperature °F")
    .elasticX(true)
    .height(400)
    .group(temperatures)
    .elasticY(true)
    .yAxisLabel("Count")
    .renderHorizontalGridLines(true);

dc.renderAll();

</script>
</body>
</html>

Modified http://nickqizhu.github.io/dc.js/js/d3.js to a secure url

Modified http://nickqizhu.github.io/dc.js/js/crossfilter.js to a secure url

Modified http://nickqizhu.github.io/dc.js/js/dc.js to a secure url

https://nickqizhu.github.io/dc.js/js/d3.js

https://nickqizhu.github.io/dc.js/js/crossfilter.js

https://nickqizhu.github.io/dc.js/js/dc.js