I think this is used for quickly checking parts for dimension. The button on the right moves the anvil away so that you can place a part in the gap quickly without changing the setting. The window with the arrow indicates if the part is larger or smaller than the setting.
We call the round building the "trash can". When we went to UCLA, we called it that. At that time, it was a Holiday Inn hotel. I think it might still be a hotel (not Holiday Inn). Just behind the trash can and to the left is the Getty Museum.