in Venice, where two influential Helmontians lived: the German physician Otto Tachenius and the Maceratese Ludovico Conti. There is also evidence that Helmontian iatrochemistry was widely diffused in Naples, as attested in the works of two prominent physicians, Lucantonio Porzio and Lionardo di Capua. In Germany, van Helmont's philosophy was already a matter of dispute by 1649, and despite censures, Helmontianism gained a large number of followers in Germany. In France, van Helmont's works were immediately perceived as a threat to classical medicine. Guy Patin, a strenuous opponent of chemistry and champion of Greek medicine, sharply attacked van Helmont, while J. Didier published a Refutation de la doctrine nouvelle du Sieur Helmont touchant es fievres at Sedan in 1653, and, four years later, Helmontian iatrochemistry was censured in a book published by the Paris physician Gabriel Fontaine. Possibly being one of the most famous physicians of the 17th and 18th centuries, Herman Boerhaave (1668–1738) approached phenomena in medicine with a scientific process of observation and experiments. He is most famous for recreating the Andrea Vesalius book of human anatomy. Boerhaave featured human beings participating in daily activities but with a transparency to them so that their organs could be seen. His fascination with chemistry led him to model the human body in terms of its chemistry in the flows and interactions of the different phases including solids, liquids and gases. In his work, he narrowed down the causes of diseases to a substance called "acid humour," which would affect flow of blood causing unbalance and detrimental chemical reactions, eventually causing malfunctioning of the human body. In a different example, it is documented that Boerhaave observed a certain "medullary oil" existed inside of bones which was very important for creating the "heat and vital motion" disturbances that could lead to an ill state of the body. A certain accumulation of a fluid in these joints of the body would lead to disastrous stagnancy which would be characterized eventually by gangrenous or unhealthy tissue where this occurred. This medical state was coined as "imposthumation." Boerhaave is, perhaps, most well known in the realm of iatrochemistry for his discussions and understanding of the nervous system. Historians believe that Boerhaave's understanding of the human body and mechanisms in relation to the nervous and physical anatomy came from his personal interactions with soldiers in wars between the Dutch and Spanish. Through his understanding of the