multiple layers: gridLayer and tileLayer by wboykinm

index.html

<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Burlington Geographic - Physical Maps</title>

<meta name='viewport' content='width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no' />
<link href='https://api.tiles.mapbox.com/mapbox.js/v1.6.2/mapbox.css' rel='stylesheet' />
<link href="//netdna.bootstrapcdn.com/bootswatch/3.1.1/yeti/bootstrap.min.css" rel="stylesheet">

<style>
  body { margin:0; padding:0; }
  #map { position:absolute; top:0; bottom:0; width:100%; }
  .leaflet-top-pane {
    pointer-events: none;
  }
</style>
</head>
<body>


<style>
#map-ui {
    position: absolute;
    top: 15px;
    right: 10px;
    margin: 0;
    padding: 0;
    z-index: 100;
    background: #fff;
}
#layerControls {
    padding: 10px;
}
</style>

<div id='map-ui'>
    <div id='layerControls' class="btn-group-vertical" ></div>
</div>
<div id='map'></div>

<script src='//api.tiles.mapbox.com/mapbox.js/v1.6.2/mapbox.js'></script>
<script src="//d3js.org/topojson.v1.min.js"></script> 

<script>
var map = L.map('map').setView([44.475, -73.212], 10);

var baseLayer = new L.mapbox.tileLayer('landplanner.hl6099hm').addTo(map);

var ui = document.getElementById('layerControls');

// Define the layers for the map
addLayer(L.mapbox.tileLayer('vanhoesenj.VTBedrock'), 'Bedrock Geology', 1);
addLayer(L.mapbox.tileLayer('vanhoesenj.VtSurfGeo'), 'Surficial Geology', 2);
addLayer(L.mapbox.tileLayer('landplanner.hli55fb7'), 'Soil Types', 3);
addLayer(L.tileLayer('https://s3.amazonaws.com/geosprocket/btvgeographic/{z}/{x}/{y}.png'), 'Elevation Contours', 4);

function addLayer(layer, name, zIndex) {
    layer
        .setZIndex(zIndex);

    // Create a simple layer switcher that toggles layers on
    // and off.
    var link = document.createElement('a');

    // Define button element properties
    link.href = '#';
    link.className = 'btn btn-primary';
    link.type = 'button';
    link.innerHTML = name;

    // Update map and element properties by selected layer
    link.onclick = function(e) {
        e.preventDefault();
        e.stopPropagation();

        if (map.hasLayer(layer)) {
            map.removeLayer(layer);
            this.className = 'btn btn-primary';
        } else {
            map.addLayer(layer);
            this.className = 'active btn btn-primary';
        }
    };

    ui.appendChild(link);
}

// Add a reference overlay
var topPane = map._createPane('leaflet-top-pane', map.getPanes().mapPane);
var topLayer = new L.mapbox.tileLayer('landplanner.hl60jemk', {
  maxZoom: 18
}).addTo(map);
topPane.appendChild(topLayer.getContainer());
topLayer.setZIndex(7);
</script>


</body>
</html>