Vitruvius’s Auger and Galileo’s Bones: Paradigms of Limits to Size in Design

Although scale effects have been known since ancient times to limit the size of structures, there has been a persistence of design errors evidently attributable to an ignorance or disregard of this limitation. Two classic case studies, one from Vitruvius and one from Galileo, of scale effects leading to failures are presented as paradigms for this genre of human error, and the repetition of it in a variety of major present-day designs is discussed. The value of the paradigms is seen to be in making the scale effect more prominent in the consciousness of students and young practitioners engaged in the process of design, thereby reducing the potential for ignoring or forgetting that successful designs cannot be scaled up indefinitely.