of all the muscles of the body a principle which is an exciting 

 cause of contractions, there are no contractions produced, be- 

 cause the quantity of that principle is not sufficient, or because 

 the resistance to contractions in many muscles is greater than in 

 the heart. 



I must, in conclusion, say, that I do not advance my theory of 

 the rhythmical movements as perfectly proved. I believe it is 

 true, and that there are a great many facts which appear posi- 

 tively to prove it. What I can assert is, that it is by far much 

 more in harmony with all the known facts, than the other theories. 



