diff --git a/data/imagery.json b/data/imagery.json
index 9eb217552..2951ce37c 100644
--- a/data/imagery.json
+++ b/data/imagery.json
@@ -7658,6 +7658,7 @@
     {
         "name": "Locator Overlay",
         "type": "tms",
+        "description": "Shows major features to help orient you.",
         "template": "http://{switch:a,b,c}.tiles.mapbox.com/v3/openstreetmap.map-btyhiati/{zoom}/{x}/{y}.png",
         "scaleExtent": [
             0,
@@ -7687,6 +7688,41 @@
         "template": "http://oatile{switch:1,2,3,4}.mqcdn.com/tiles/1.0.0/sat/{zoom}/{x}/{y}.png",
         "default": true
     },
+    {
+        "name": "NLS - Bartholomew Half Inch, 1897-1907",
+        "type": "tms",
+        "template": "http://geo.nls.uk/mapdata2/bartholomew/great_britain/{zoom}/{x}/{-y}.png",
+        "scaleExtent": [
+            0,
+            15
+        ],
+        "polygon": [
+            [
+                [
+                    -9,
+                    49.8
+                ],
+                [
+                    -9,
+                    61.1
+                ],
+                [
+                    1.9,
+                    61.1
+                ],
+                [
+                    1.9,
+                    49.8
+                ],
+                [
+                    -9,
+                    49.8
+                ]
+            ]
+        ],
+        "terms_url": "http://geo.nls.uk/maps/",
+        "terms_text": "National Library of Scotland Historic Maps"
+    },
     {
         "name": "NLS - OS 1-inch 7th Series 1955-61",
         "type": "tms",
@@ -13915,6 +13951,7 @@
     {
         "name": "OpenStreetMap GPS traces",
         "type": "tms",
+        "description": "Public GPS traces uploaded to OpenStreetMap.",
         "template": "http://{switch:a,b,c}.gps-tile.openstreetmap.org/lines/{zoom}/{x}/{y}.png",
         "scaleExtent": [
             0,
diff --git a/data/update_imagery.js b/data/update_imagery.js
index 5611f003e..920436166 100644
--- a/data/update_imagery.js
+++ b/data/update_imagery.js
@@ -19,7 +19,7 @@ var censor = {
     "Public Transport (\u00d6PNV)": true // https://github.com/osmlab/editor-imagery-index/issues/15
 };
 
-var description = {
+var descriptions = {
     'MapBox Satellite': 'Satellite and aerial imagery.',
     'OpenStreetMap (Mapnik)': 'The default OpenStreetMap layer.',
     'TIGER 2012 Roads Overlay': 'Public domain road data from the US Government.',
@@ -38,7 +38,8 @@ sources.forEach(function(source) {
         type: source.type
     };
 
-    if (description[im.name]) im.description = description[im.name];
+    var description = source.description || descriptions[im.name];
+    if (description) im.description = description;
 
     im.template = source.url;