diff --git a/README.md b/README.md
index f93cefd..21a6464 100644
--- a/README.md
+++ b/README.md
@@ -6,6 +6,10 @@ Works well in Chrome and Firefox; not tested in Internet Exploder.
 
 ![what it should look like](resources/public/images/example.png)
 
+## Demo site
+
+There's a demo site [here](https://simon-brooke.github.io/swinging-needle-meter/resources/public/index.html).
+
 ## Intended uses
 
 This is a component for a console, typically one controlling a technical or scientific instrument. It is
diff --git a/resources/public/index.html b/resources/public/index.html
index 6cb5b26..17b0222 100644
--- a/resources/public/index.html
+++ b/resources/public/index.html
@@ -11,7 +11,15 @@
     <title>Example swinging needle meter following re-com conventions.</title>
   </head>
   <body>
-    <div id="app"></div>
+    <div id="app">
+      <h1>
+        Please be patient...
+      </h1>
+      <p>
+        If you're seeing this, Javascript has not yet loaded. If you continue
+        to see this for more than a minute, it may be that something has broken.
+      </p>
+    </div>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/snap.svg/0.5.1/snap.svg-min.js"></script>
     <script src="js/compiled/app.js"></script>
     <script>swinging_needle_meter.core.init();</script>
