The rules at a particular university were
such that if the professor were not present in the classroom by 15 minutes past the hour,
the class was considered a "walk" and the students were free to leave, with no
penalties for missing a class. The rooms were equipped with the type wall clocks which
"jumped" ahead each minute, in a very noticeable fashion. As it were, these
clocks were also not of the most sophisticated construction. Some enterprising student
discovered that if one were to hit the clock with chalkboard erasers, it would cause the
clock to "jump" ahead 1 minute.
So, it became almost daily practice for
these students to take target practice at the clock (as it would have it, this particular
professor was not the most punctual, and the students considered him severely
"absent-minded"). A few well aimed erasers, and lo, 15 minutes were passed, and
class dismissed itself.
Well, when the day for the next exam rolled
around, the professor strolled into the room, passed out the exams, and told them,
"You have 1 hour to complete the exam."
The professor then proceeded to collect the
erasers from around the room, gleefully took aim at the clock. When he had successfully
"jumped" the clock forward 1 hour, he closed the class and collected the exam
papers.
