76 OF VITAL MOTION. 



tractions on irritation, and of rigor mortis, are facts 

 which show that the muscles still preserve the power 

 of contracting. There is no reason for supposing that 

 the paralysed part is more relaxed than it was when 

 the nerves retained their integrity; indeed, so far 

 from this, the contrary may be argued from the 

 atrophy and shrinking of the tissues, which date 

 from the time of the lesion. It is the same also in 

 regard to the paralysis of motion which has been 

 induced experimentally by the division of nerves, or 

 by the removal of nervous centres. Tonic rigidity 

 of the muscles is a common consequence of violent 

 destruction of the cerebro-spinal ganglia; and where 

 this is not the result there is no reason whatever for 

 supposing the muscles to be more relaxed than they 

 were before the operation. The contractions which 

 take place under the operation of galvanism, and after 

 death, are sufficient proofs that there is still a possi- 

 bility of contraction in the paralysed muscle. And, 

 lastly, it is shown, in the last paper contributed by 

 Matteucci to the Transactions of the Royal Society, 

 that the contractions induced by galvanism in the 

 hinder limbs of a frog, after the division of the spinal 

 cord, are more powerful than in an animal of similar 

 magnitude and strength in which the cord is intact : 

 an observation which is calculated to show in a very 

 strong light the non-necessity of an additional supply 

 of nervous influence in the phenomena of contraction. 



