My post went away... Could I salvage the old version from the blockchain?

I wrote a detailed post about what dinosaurs sounded like based on what we know about them and all... I published it and then while I was rereading it, I noticed two spelling error, so I hit the Edit button and fixed the spelling. To my surprise and disappointment my post had been replaced with a few symbols signifying my edit, but none of my original post.

Is there a way to check the block chain and take out my old version so I can post it properly?