Caused by this overflowed comment which isn't line-broken.
Your table layout sucks! shakes fist
The comment in question was made in this posting.
The problem is nothing to do with line breaks. It is due to the fact that Kris failed to include the http:// component of the URL. (NB — I am using Chrome as my browser.)
This is how he/she formatted it:
books.google.com/ngrams/graph?content=runaway+&year_start=1800&year_end=2000&corpus=15&smoothing=3&share=&direct_url=t2%3B%2Crunaway%20%3B%2Cc0%3B%2Cs0%3B%3Brunaway%20slaves%3B%2Cc0%3B%3Brunaway%20slave%3B%2Cc0%3B%3Brunaway%20horse%3B%2Cc0%3B%3Brunaway%20negroes%3B%2Cc0%3B%3Brunaway%20inflation%3B%2Cc0%3B%3Brunaway%20match%3B%2Cc0%3B%3Brunaway%20from%3B%2Cc0%3B%3Brunaway%20horses%3B%2Cc0%3B%3Brunaway%20and%3B%2Cc0%3B%3Brunaway%20servant%3B%2Cc0
Appended as a comment below is the same link, this time including the http:// prefix.