296 PROFESSOR MATTEUCCI’S ELECTRO-PHYSIOLOGICAL RESEARCHES. 
from the nervous extremities towards the brain. We must bear in mind that it has 
been demonstrated by direct experiments, that when an electric current is propagated 
in a muscle, this current never quits the muscular fibre in order to pass into the ner- 
vous filaments. It is therefore perfectly evident that the phenomena of which we 
have spoken, excited by the passage of the electrical current through a mass of living 
muscle, are exclusively owing to the influence of electrical states propagated in the 
muscles upon the nervous force contained in the nerves. To speak with more pre- 
cision, we should say thus : it is demonstrated by experiment that an electric current 
transmitted through a living mass of muscle in the same direction as its nervous 
ramification, developes a nervous current* which is propagated in the direction of the 
ramification of the nerve, and which reaches to its extremities ; if the electric current 
pass in a contrary direction to that of the ramification of the nerve, the nervous cur- 
rent which it developes follows the same direction, that is, from the extremity of the 
nerve towards the brain. 
The great importance of the conclusions drawn from these experiments consists in 
this, that they lead to the same law which establishes the analogy between nervous 
force and the electrical discharge of fishes. 
We obtain an electrical discharge in fishes, when we produce a nervous current by 
stimulating the nerve which communicates with the organ. In experimenting on 
living animals, we produce a nervous current by the electric discharge which we 
transmit through the muscles. When this discharge is directed through the muscle 
in such a way as that the positive and negative states of electricity are disposed 
relatively to the ramification of the nerves, as in the discharge of electrical fishes, a 
nervous current is produced by the influence of the electric current having the same 
direction in both cases ; in the torpedo, the nervous current produces the electrical 
states ; in the muscular fibre, the nervous current is produced by the influence of the 
electric current. 
Following up the analogy, we are led to expeet that when the electric current tra- 
verses a muscular mass in a contrary direction to that of the ramification of the 
nerve, it would produce a nervous current in an opposite direction to that which is 
developed by the electric current passing along the muscle in the same direction as 
the ramification of the nerves. This is a conclusion the truth of which is clearly 
demonstrated by the phenomena of sensation or of pain, which are produced by the 
passage of the electric current in a contrary direction to that of the ramification of 
the nerves. 
Satisfied to go forward with a slow but sure step in the vast and very obscure 
field of electro-physiological science, I cannot but regard as highly important the 
discovery set forth at the close of this memoir, of the strict correlation existing be- 
tween the electric current and nervous force. 
Pisa, June J849. 
