In the last twenty years of the nineteenth century in Italy, the scientific bases are set in order to give birth to industrial/physical medicine. Physiology, hygiene and pathology deal with topics/matters/subjects bound to the working environment. Angelo Mosso deepens the studies, already begun in the 70s by Ugo Kronaker in Leipzig, about muscular strain by publishing these researches with two different purposes. The scientific and the popular one. The book La fatica, written in 1891, gathers the results of the researches on the muscular fatigue, examined from the physiological and psychological point of view, as strain caused by the continuous and close attention. A scientific treatise that builds the foundation of modern ergonomic. Mosso then considers the physical effects of fatigue coming up to the extreme cases of some groups of workers, such as those engaged in the extraction of sulfur in Sicily, through the acceptance of more and more miserable wages, compelled by necessity, they are forced to work in inhuman conditions. This downward work offer is defined by Mosso as ergomachia. This struggle leads after short time the worker to exhaustion of strength, untill reaching a severe, permanent and irriversible debilitation. Forces the worker, until anyone reach a state of severe pathological physical debilitation permanent and irreversible.