Until not long ago, these cannons were placed in front of the Meyer Hall of Science.
At some moment in the early 2000s the Physics Dpt had a plenary talk by Gerardus 't Hooft, Dutch Nobel Prize winner. As I was interested by some entanglement problems, I tried to present our distinguished speaker some of my thoughts. I was talking to him along the road from the dining area to Meyer, and as we passed the cannons, he stopped for a while, looked at the cannons and told me he felt that the presence of such symbols in front of a university building was not a nice combination, since it reflects hostility. Honestly I did not pay much attention to the cannons, but I agreed with him.
Recently they were moved near a lake on campus (pictured here).