Very basic question: how to embed on WordPress?

[Christopher M. Johnson]

Hi, I've followed all of the steps on your site, but when I put the embed code that's generated at http://timeline.knightlab.com/ (which I'm assuming is the code in the gray box at Step 4) into WordPress text editor, nothing happens. Just a huge blank space. 

Am I missing something? Do I need to install GitHub's widget, or can I do this without the widget? 

Their page - https://github.com/NUKnightLab/TimelineJS#using-inline-easiest - doesn't make that clear at all.

Please help! The spreadsheet took a lot of time to put together, and it works when I preview it on your site, but not on OUR site.

Thanks a lot,

Christopher.