Recto: a drawing of the head and shoulders of a bald man turned in profile to the right, and a bulgng eye traced from the verso. This is surrounded by mathematical calculations. Below are four lines of writing in Leonardo's hand. Verso: the same head traced from the recto, and a small grotesque head, in profile to the right.

The disdainful expression of the main figure is deflated by the rapidly sketched grotesque that gazes up at him from heavy-lidded bulging eyes. An opposition of types may have been intended to some degree - aquiline against snub nose, hideously long upper lip against tightly compact mouth - but this is not fully cogitated and cannot have been the main reason for drawing either figure. The addition of the grotesque was a simple visual joke, the work of no more than a few seconds.