from a nervous packet, in the manner 

 before mentioned, though too minute to 

 admit of further subdivision, appear by 

 the microscope to be themselves packets 

 of smaller threads. It is generally as- 

 serted by microscopical observers, that 

 the nerves and medullary matter of the 

 brain and spinal marrow are the same, 

 and are composed of very minute fibres. 

 Fontana speaks confidently on this point ; 

 and he further says, that he has seen these 

 nervous fibres regenerated in th^ medium 

 which has been formed to unite a divid- 

 ed nerve. He describes the nervous 

 fibres in every part of the nervous sys- 

 tem as cylindrical, pursuing a slightly un- 

 dulating course, and being in a consi- 

 derable degree transparent. He states 

 also that they are larger than the ulti- 

 mate fibres of muscles. 







. 



Microscopical observers also tell us, that 



