Secreting Power of Animals. 557 



as happens with respect to the power of the heart, when ic 

 suffers from injury of the brain and spinal marrow, the secreting 

 power would be deranged; but we find its derangement bearing 

 no proportion to the injury done to the nerves, but always pro- 

 portioned to the degree in which the supply of nervous influence 

 is impaired. 



Besides if the division of the nerves produces its effect by 

 injuring the secreting organs, although the nervous influence 

 were again restored to them, they should still be found inca- 

 pable of their function. But it has been ascertained by the 

 experiments of Dr. Haighton, related in the Philosophical Trans- 

 actions of 1795, that, if the secreting surface is not so far 

 deranged by the division of the nerves as to prove fatal, as 

 soon as the parts of the nerves are sufficiently reunited, again 

 to convey the nervous influence, the secreting power again be- 

 comes perfect. Will it be alleged, that as the division of the 

 nerves injures the secreting organ, their re-union repairs the 

 injury ? or that by some strange coincidence the injury done to 

 the secreting surface in such cases requires exactly the same 

 time for its repair, which is required for the re-union of the 

 nerve, although the two events are no ways connected ? 



Tlie question before us is, when the function of a secreting 

 surface is deranged by dividing its nerves, is this to be ascribed 

 to its being deprived of its nervous influence, or to its being 

 injured by the act of dividing its nerves ? We know that it 

 arises from the former, because when it is deprived of its ner- 

 vous influence by any other means the effect is the same ; be- 

 cause the effect is not at all proportioned to the degree of in- 

 jury done to the nerves, but to the degree in which the nervous 

 influence is withdrawn ; and because as soon as the nervous 

 influence is restored, it is again capable of its function. 



I may here observe that in one essential respect Dr. Alison 

 in a paper above referred to, misconceives the result of my ex- 

 periments. I never found the secretions suppressed, as Dr. 

 Alison supposes, by dividing the nerves ; so far from it that it 

 is observed in the 124tli page of the second edition o*" the 

 " Iruiuiry," &c. ; " It deserves notice that although the eighth 



Vol.. IX. R 



