H e was drilling a small hole in the panel. For the past few weeks he had painted the panel with utmost concentration. The painting was of the Florence Baptistry and its surrounding, as it looked when seen from the Cathedral. There was something special in this painting when compared to all other paintings of that time. Once done, he set the panel to face the view that inspired it. Now he stood behind the panel and leaned forward to peep through the hole. For an onlooker, all this might have looked crazy, or even worse he or she would have accused this painter of plotting something shady. As he was peeping through the hole, Brunelleschi picks up a mirror and holds the mirror at arm's length, in front of the panel. Now he was able to see the reflection of the painting in the mirror. As he continued to view through the hole, he moved the mirror in and out of his line of sight. It was now clear that he was trying to compare his painting to the real Baptistery. But...