There's a button in the editor - top row, number 3 from the left - that if you hover over shows "Insert Image"
It adds this code: [img ][/img ] (without any spaces). Put the full path (
https://www.flickr.com/photos/39342778@N07/14433122969/) in between the brackets, and voila!
Hmmmm. Not showing up.
But that's how it works - promise!