LIFE AND WORKS OF NICOLAUS STENO XIX 



Finally Steno was the first to show that contraction of a muscle 

 might occur not only by stimulation of its nerve, but also by stimu* 

 lation of the muscle itself. 



At an early period Steno became interested in the study of the brain. The Brain. 

 This is evident from a Letter to Thomas Bartholin, dated March 1663, 

 in which he speaks about his having made numerous dissections of 

 this organ, adding that what he found through these dissections was 

 in every respect inconsistent with what Descartes taught about the 

 brain. It is quite natural that Steno should become interested in the 

 study of this organ. He was a pupil and friend of Sylvius, with whom 

 he was almost in daily intercourse, and Descartes' De Homine, which 

 had just appeared, had made an enormous sensation. It is easy to 

 understand that Steno, when first mentioning Descartes, takes up a 

 critical position towards this work, and more especially towards that 

 part of it which deals with the brain. Steno clearly saw that nearly 

 all the anatomical descriptions and physiological explanations of Des= 

 cartes' were quite erroneous, and he was certainly at too close a range 

 to be able to fully understand the idea of this particular work. 



The interest Steno took in the brain and its function might rationally 

 lead one to suppose that he published his numerous observations 

 on this organ. Strictly speaking this never happened, though during 

 his stay in Paris he delivered a Discourse on the Brain before the as* 

 sembly of learned men, who met at Thevenot's. This Discourse, which 

 scarcely contains a single new observation, he left in Paris when 

 leaving that city, and it was not published till four years after by 

 a Paris bookseller. Steno seems purposely to leave the results of his 

 own researches out of the question, and when this little work still 

 ranks among his most important ones, it is because it contains in* 

 structions concerning the study of the brain in particular, and the 

 study of natural science in general, so intelligent and so sound that 

 an anatomist like Winslev — who by the way was a relative and 

 countryman of Steno's and like him a convertite to Catholicism — 

 many years afterwards admits, que le seul Discours de feu M. Stenon 

 sur I'Anatomie du Cerveau, a ete la source primitive &■ le modele general 

 de toute ma conduite dansles travaux Anatomiques, and even goes so far 

 as to reprint the whole of the Discourse in all editions of his famous 

 Anatomy. Much of Steno's Discourse was, in fact, of so far«sighted 

 a nature that it was not till many years after Winslev's time, partly 

 not till our own age, that scientists were able to follow the instructions '"> 

 given by Steno. It would carry us too far to give any detailed account 

 of the Treatise; but in order to duly appreciate it, it will be necessary 

 to remind the reader of the views current in the days of Steno concerning 

 the brain and its function. The anatomical observations of the brain 

 were still rather rudimentary, and its physiology was greatly based on 



