Unfortunately, the download links to the PDF files for Things That Make You Go Hmmm... are non-functioning today. I have notified the developers who are working to fix the issue as quickly as possible. In the meantime, letters can still be read inside your browser.
My sincere apologies for this inconvenience. The Gremlins clearly have it in for me.
I will notify you as soon as the issue is fixed.
Many thanks for your patience