In old cameras you could double expose the negative by forgetting to wind the film on to the next frame. This is what has happened here, because you can see the ship masts and rigging superimposed on the photo taken in the hall. So it's not the best quality photo, but is included because so far as I know, this is the only photo that shows an exam in progress. How many of you remember with dread the exam days? A rule and pencil case, slide rule and log tables was all that alowed in the room with you!