diff --git a/README.md b/README.md
index 6a4961a..3ef9c04 100644
--- a/README.md
+++ b/README.md
@@ -499,6 +499,13 @@ By default, Reveal is configured with [highlight.js](http://softwaremaniacs.org/
 </section>
 ```
 
+### Slide number
+If you would like to display the page number of the current slide you can do so using the ```slideNumber``` configuration value.
+
+```javascript
+Reveal.configure({ slideNumber: true });
+```
+
 
 ### Overview mode
 
diff --git a/test/test.js b/test/test.js
index 36983c8..f620b5b 100644
--- a/test/test.js
+++ b/test/test.js
@@ -11,6 +11,22 @@
 
 Reveal.addEventListener( 'ready', function() {
 
+	// ---------------------------------------------------------------
+	// DOM TESTS
+
+	QUnit.module( 'DOM' );
+
+	test( 'Initial slides classes', function() {
+		var horizontalSlides = document.querySelectorAll( '.reveal .slides>section' )
+
+		strictEqual( document.querySelectorAll( '.reveal .slides section.past' ).length, 0, 'no .past slides' );
+		strictEqual( document.querySelectorAll( '.reveal .slides section.present' ).length, 1, 'one .present slide' );
+		strictEqual( document.querySelectorAll( '.reveal .slides>section.future' ).length, horizontalSlides.length - 1, 'remaining horizontal slides are .future' );
+
+		strictEqual( document.querySelectorAll( '.reveal .slides section.stack' ).length, 2, 'two .stacks' );
+
+		ok( document.querySelectorAll( '.reveal .slides section.stack' )[0].querySelectorAll( '.future' ).length > 0, 'vertical slides are given .future' );
+	});
 
 	// ---------------------------------------------------------------
 	// API TESTS