He plays with space in an interesting way in this piece. He uses different shapes to create a visual illusion. When the painting is looked at directly, it appears that it is in motion.
Klee wrote and published extensively on colour theory. It was one of his favourite topics. In his work, he often looked at new ways of using pigments to communicate whatever he wanted to say.
In many pieces, he combines this with Abstract forms to paint images that are both visually appealing and invite further thought.
Darker colours are used in Fire At Full Moon. They are pleasing to the eye and relaxing to look at. In a way, the final effect of the painting produced with geometric shapes is like a tapestry. Whether in large scale or miniature, this piece would bring a feeling of comfort to any observer.
Klee creates the illusion of movement by carefully laying out shapes that have their lines slightly angled away from the viewer's line of sight.
A further sense of unsteadiness is gained by doing this in several sections of the painting. The final effect is one of constant motion in different sections of the piece.
Klee may be introducing this sense of change for several reasons. The usual sense that greets a person during a full moon is that something remarkable is happening. These occurrences are fascinating and mark a time of change. In fact in many cultures, the full moon is accompanied by superstition.
Full moons are seen as times of wakening or times of possibility. It is as though even the very state of nature is in flux. For this reason, folk tales such as those associated with creatures changing shape are told and retold.
Klee has brought this to mind here with the transforming patterns used in this work, which seems to say that the very substance of reality is unsteady.
This message is not meant to frighten the observer. Instead, by using cool colours, Klee indicates that a time of change is to bring comfort. It offers the opportunity to do things differently, to feed the fire that rises at this time in a positive way.