Looking at MC Escher's Circle Limit IV, one sees a circle with a couple of angels and demons in it, arranged in a manner that is from bigger to smaller in reference to the center, to say the least. That is for the layman's view, mechanically speaking there is more to it than just that.
Continuum Mechanics assumes that objects in a system are continuous. In MC Escher's artwork, despite the word Limit in the title, I think that the circle is not just s simple flat disk whose edges determine its ends. If we may see, the "edges" of the circle aren't solid, meaning these may not be "edges" after all, what's in there are still a number of bodies (the angels and demons) that goes beyond what our eyes can observe, just like a 2-d version of an original.
Structural Analysis which deals with failures in structures may also be observed in this circle. Having the center of the circle as the point of reference, the parts are arranged in a manner that goes from biggest to smallest, in an alternating fashion. Disregarding how small or big a part is in relation to the system, fact remains that this part constitutes the whole. If any many of these angels or if one demon even will be removed from the system, a change in operation will definitely take place. With one part missing, the system cannot work as efficiently or worse may not function at all.
Assuming that the circle is a machine, the motion of parts in the system in relation to the forces that causes this motion shall be held important. The design of the machine and shall be based on a very accurate analysis of different factors: the mass of the parts, the forces that act on these bodies and the arrangement and precise measurement of each. These factors are used to find the desired range of motion for MC Escher's circle, for smooth operation.
