Looking at that site (In chromes view source), line 1 also contains minified (spaces / line breaks removed) references the JavaScript files. In Chrome console, the error I’m receiving is:
Uncaught TypeError: Object [object Object] has no method 'slides'
The error is caused because the JavaScript is looking for #slides in what has been loaded up to that point (Which is not there). To fix it, put the JavaScript in the footer of the page, or make it run on document ready.