A Toulouse, Cehz Jean Guillemette, 1715, 4°, (12), 102, (6) pp., 6 Kupferstichtafeln mit 17 Figuren, feiner Halbledereinband. First Edition! "In 1715, the Montpellier surgeon Raymond Vieussens published his Traité nouveau de la structure de l'oreille.61 Significantly, it appeared alongside a groundbreaking work by the same author on the heart, Traité nouveaux de la structure de la Cour. Though these were completely separate treatises, Vieussens explained that he followed the same model of investigation in each work. This involved exploring physical-mechanical processes of "natural movement" surrounding both the heart and ear. Of all the senses, the ear most resembled the heart because it was a solid mechanism whose movement depended on the "esprit animal," the life force of the body entering inside the mechanism via an external anatomical part (the external ear). In his support of the "esprit animal," Vieussens followed the work of Thomas Willis. However, Vieussens' emphasis on bodily fluids and solids (arteries, air from breathing and received through the skin), rather than the nervous system of the brain, anticipated the later work by Théophile de Bordeu, another famous Montpellier doctor, on the pulse.63 For Bordeu, the pulse constructed its own rational trajectory throughout the human body according to bodily illness. In his treatise on the ear, Vieussens explained that since he found Duverney's treatise too difficult to understand, he aimed in his own work to give a clearer idea of the different parts, how they were constructed, and also to recognize the particular tissue in each part and their "marvellous" shape. He also sought to demonstrate in a much clearer fashion how each part communicated with each other. This has only been possible, he explained, after looking at the structure over a thousand times. Vieussens intended his description of the ear to be easy to memorize. It has the quality of a medical textbook. The centerpiece was the muscles of the inner ear which were mechanically interconnected. He was eager to explain that tinnitus and deafness were caused by the violent movement of these muscles, not by unwanted air caught in the cavities. He placed the components surrounding the eardrum together (malleus, incus, stapes, os orbiculaire) which formed a space of "natural equilibrium." The auditory nerves in the different cavities of the labyrinth formed a different section. The labyrinth and cochlea were coupled together into a third section. Finally, Vieussens connected l'esprit animal with the sensation of hearing. This was done by describing the way in which the mechanical parts were "shocked" into action. Like the movement of the heart, their movements operated exactly in proportion to that level of force provided by the fluid. Sensory mechanisms were far from passive reflex movements. They were intimately connected to a constantly circulating internal and externally channelled fluid force. The brain was far too soft to be involved, since it collapsed at the impact of the shock. According to Vieussens, hearing was considered pivotal to the understanding of life forces. It encapsulated the essence of the living body in motion." Penelope Gouk* and Ingrid Sykes: Hearing Science in Mid-Eighteenth-Century Britain and France. J Hist Med Allied Sci. 2011 Oct; 66(4): 507-545. See- Albert Mudry, The History of Otology (2015), pp.260-265; Poltizer, Geschichte der Ohrenheilkunde I (1907), pp.275-279, Portrait.