The definition of a GNOMMON is the projecting piece on a sundial that shows the time by the position of its shadow. Based on the concept of an analemmatic sundial, this project is a performative drawing exercise of the shadows projected by oneself on to a large piece of paper while facing north. In this way, the body becomes the instrument to measure the passage of time.

Black ink (one in pure state and one 50% diluted with water) is used to mark the difference in the time intervals between every round of drawings.
 
What is the analemmatic sundial theory?
 
“In an analemmatic sundial the pointer is vertical. The shadow cast by the sun on a horizontal surface, such as the ground, moves clockwise around the pointer, but this time it varies in length during the day. The endpoint of the shadow no longer falls on a circle.” Ref : (Plus.Maths)