diff --git a/CHANGELOG.md b/CHANGELOG.md
index 59048823..6255e4ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+v0.6.68
+* [scalebar] giving a pair of distances creates a dual-unit scale bar (style b only).
+* [web] minor bug fixes and improvements.
+
 v0.6.67
 * -rectangle command with width=<size> option creates a "frame" layer to use as the extent of an SVG map by setting the size of the SVG viewport (an alternative to using -o fit-extent=<size> option).
 * [web] Map symbols scale as the map zooms when a frame layer is visible.
diff --git a/REFERENCE.md b/REFERENCE.md
index 3bd71cbf..cba3c281 100644
--- a/REFERENCE.md
+++ b/REFERENCE.md
@@ -615,7 +615,7 @@ Polyline layers
 Polygon, polyline and point layers
 - `this.partCount` 1 for single-part features, >1 for multi-part features, 0 for null features
 - `this.isNull` True if feature has null geometry
-- `this.bounds` Bounding box as array [xmin, ymin, xmax, ymax]
+- `this.bbox` Bounding box as array [xmin, ymin, xmax, ymax]
 - `this.width` Width of bounding box
 - `this.height` Height of bounding box
 
@@ -1142,7 +1142,7 @@ Add a scale bar to an SVG map. The command creates a data-only layer containing
 
 The length of the scale bar reflects the scale in the center of the map's rectangular frame.
 
-`<label>` or `label=` Optional label giving the size and units of the scalebar, e.g. `"25 k.m."`. If only units are given, a length will be assigned. If the `label` property is missing, scale bar properties will be auto-generated.
+`<label>` or `label=` Optional label giving the size and units of the scalebar, e.g. `"25 k.m."`. If only units are given, a length will be assigned. If the `label` property is missing, scale bar properties will be auto-generated. If two lengths are given (e.g. `1000 km,500 miles`), a dual-unit bar will be generated, if the scale bar style supports it.
 
 `style=` Scalebar style, `a` or `b`. Style `b` has tic marks.
 
diff --git a/package-lock.json b/package-lock.json
index 60d8c089..b2992e85 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "mapshaper",
-  "version": "0.6.67",
+  "version": "0.6.68",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "mapshaper",
-      "version": "0.6.67",
+      "version": "0.6.68",
       "license": "MPL-2.0",
       "dependencies": {
         "@placemarkio/tokml": "^0.3.3",
diff --git a/package.json b/package.json
index e013f472..78f21153 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mapshaper",
-  "version": "0.6.67",
+  "version": "0.6.68",
   "description": "A tool for editing vector datasets for mapping and GIS.",
   "keywords": [
     "shapefile",
diff --git a/src/cli/mapshaper-options.mjs b/src/cli/mapshaper-options.mjs
index f12d98b8..ebbf3f62 100644
--- a/src/cli/mapshaper-options.mjs
+++ b/src/cli/mapshaper-options.mjs
@@ -2018,7 +2018,11 @@ export function getOptionParser() {
       describe: 'e.g. bottom-right (default is top-left)'
     })
     .option('label-position', {
-      describe: 'top or bottom'
+      describe: 'top, bottom, top-center (style a), etc'
+    })
+    .option('dual-units', {
+      // describe: 'display both metric and imperial units',
+      type: 'flag'
     })
     .option('margin', {
       describe: 'offset in pixels from edge of map',
diff --git a/src/dissolve/mapshaper-polygon-dissolve2.mjs b/src/dissolve/mapshaper-polygon-dissolve2.mjs
index 54049226..dff7a6aa 100644
--- a/src/dissolve/mapshaper-polygon-dissolve2.mjs
+++ b/src/dissolve/mapshaper-polygon-dissolve2.mjs
@@ -60,9 +60,10 @@ function groupPolygons2(lyr, getGroupId) {
 
 function getGapRemovalMessage(removed, retained, areaLabel) {
   var msg;
+  var tot = removed + retained;
   if (removed > 0 === false) return '';
-  return utils.format('Removed %,d / %,d sliver%s using %s',
-      removed, removed + retained, utils.pluralSuffix(removed), areaLabel);
+  return utils.format('Removed %,d of %,d sliver%s using %s',
+      removed, tot, utils.pluralSuffix(tot), areaLabel);
 }
 
 export function dissolvePolygonGroups2(groups, lyr, dataset, opts) {
diff --git a/test/each-test.mjs b/test/each-test.mjs
index a265078f..58ae0b9d 100644
--- a/test/each-test.mjs
+++ b/test/each-test.mjs
@@ -342,12 +342,12 @@ describe('mapshaper-each.js', function () {
       assert.deepEqual(lyr.data.getRecords(), [{parts: 2}, {parts: 0}]);
     })
 
-    it('point this.bounds this.height this.width', function() {
+    it('point this.bbox this.height this.width', function() {
       var lyr = {
         geometry_type: 'point',
         shapes: [[[0, 2], [0, -2]], null]
       };
-      evaluateEachFeature(lyr, nullArcs, "bbox = this.bounds, h = this.height, w = this.width");
+      evaluateEachFeature(lyr, nullArcs, "bbox = this.bbox, h = this.height, w = this.width");
       assert.deepStrictEqual(lyr.data.getRecords(), [{bbox: [0,-2,0,2], h: 4, w: 0}, {bbox: [], h: 0, w: 0}]);
 
     });