<p>For a civil engineering class at my alma mater, the professor had the students survey a portion of campus, including a building on the side of a hill.</p>
<p>When the results came back, the students were marked down a grade because the location of building on the side of the hill was 7 inches off. It seems the students had the building sliding down the hill into the city below.</p>
<p>The students insisted their measurements were correct, so the professor went out and surveyed the building himself. He determined that building had in fact slid 8 inches down the hill. Since the students’ result was still wrong, he did not give them the higher grade.</p>
<p>Or so the story goes.</p>
<p>The building really was sliding down the hill, though. To fix it they dug a tunnel from the basement up the hill to the basement of another building that was resting on bedrock, and wasn’t going anywhere for a few centuries. They installed 4 twelve-inch-thick steel cables from one building to the other to prevent the downhill building from sliding any further down the hill.</p>
<p>Or so the story goes.</p>