Examinations have been made easier physically, not mentally speaking--for both student and instructor by the mechanical marker. It aids the student by eliminating the essay examination. It aids the instructor by grading the examination papers at the rate of 300 to 400 per hour.

Each student uses a graphite pencil and a special examination sheet. All he has to do is to make a pencil mark about a quarter of an inch long in one of the five answer columns accompanying each question. In the grading machine, the examination sheet is pressed against 750 both of electric contacts corresponding to the 750 answer positions on the paper. The pencil mark on any of the answer positions on the sheet closes an electric circuit, and with the graphite acting as the conductor of current, the machine automatically records whether the answers are right or wrong. A dial shows instantly the number of answers the student got right and wrong.

One of the first institutions to install this boon to the academic world was Purdue University where these pictures of the grader in action were taken.