Nope. I now understand your problem and can reproduce it.
Originally Posted by Cyanide_Pierce
If you use Chrome's web dev tools to analyse the page, on the first page load you see the following warning:
Maybe the PHP file is being transferred with the wrong MIME type?
Resource interpreted as Image but transferred with MIME type text/html: "http://www.piercemcgeough.co.uk/liveproject/index.html"
What happens if you remove the images from the PHP file and replace them with some randome text (just for testing purposes).