On April 22nd and May 6th 1752 Albrecht von Haller read two papers before the Royal Society of Sciences of Goettingen. They were published in the following year under the title: De partibus corporis humani sensibilibus et irritabilibus. This work, whose author was then forty-five years old and at the height of his fame as a professor at the newly founded University of Goettingen, is a landmark in the history of physiology in general and of muscular physiology in particular. But unlike other great scientific contributions it does not contain an entirely new discovery. For the phenomena of sensibility and irritability were known long before Haller and the very terms had been coined by others. The significance of Haller’s contribution lies in the method by which he approached the subject.
In antiquity Galen had already formulated the doctrine that all sensibility was bound to the nervous system. But since he lacked modern histological methods, his ideas about the distribution of the nervous fibers in the tissues were rather speculative. It was, therefore, a task left to later physiologists to find out which tissues actually were sensible and what was their relation to the nerves.
Galen had moreover maintained that the skeletal muscles were brought into action by the nerves which by means of the psychic pneuma effected voluntary motion through them.
(Description from INTRODUCTION BY OWSEI TEMKIN)