The Lounge is rated Safe For Work. If you're about to post something inappropriate for a shared office environment, then don't post it. No ads, no abuse, and no programming questions. Trolling, (political, climate, religious or whatever) will result in your account being removed.
Sounds like my chemistry teacher. Mr. Conrad looked like a derelict and sounded like he was a few ions short of a compound. Like yours, he was a hero. I don't know what medals he may have had, but he had a plate in his head and walked with a limp from injuries received in WWII. For all that, you didn't screw around in his class. The man was lethal with a chalkboard eraser thrown from the front of the room.
He was a great teacher. I learned enough from him that when I was required to take chemistry in college, it was a cake walk.