It was located on a college campus. Doesn’t really speak well of the college, but times were lean.

In later years this was converted to a music building; I took piano lessons here in the late 60s. Mr. Froelich taught in the room on the right; the recitals – the terrifying, sweat-soaked recitals – were held in the room on the left. All traces of its former life as a library had vanished. Except for the smell of old books, of course. Worse than that: old unread books, tomes that had never been checked out at all, and now haunted the rooms, shouting with mute fury. 

No, it was mold. I'm going with mold.

In any case, the missing Carnegie didn’t look like this, or the other picture. It looked like this. (Link to fargo-history.com. They may have won this round, but the game's not yet over!) It was a library at the other institution of higher learning, the ill-fated Fargo College.