STUDENT LIFE AND EARLY MANHOOD 



several trunks, peculiar cells or corpuscles, now 

 called nerve cells or nerve corpuscles. These cells 

 are found also in all nerve centres, such as the spinal 

 cord and brain, and they lie in a fine variety of tissue, 

 while numerous nerve fibres pass through the ganglia, 

 apparently in close proximity to the cells. No con- 

 nection between the nerve cells and the nerve fibres 

 had been discovered, although Miiller taught that 

 in all probability such a connection existed. It was/ 

 reserved to Helmholtz to make the discovery. With 

 a very simple and primitive form of a compound 

 microscope, almost as different from the splendid 

 instruments of the present day as a cheap spyglass is 

 from an astronomical telescope, he discovered in the 

 ganglia of leeches and crabs that the nerve fibre 

 originates from one of these corpuscles. This was 

 an observation of fundamental importance as showing 

 the connection between nerve fibre and nerve cell, 

 and it has been extended throughout all nerve centres. 

 The so-called axis cylinder of a nerve fibre, the 

 central part of a nerve fibre, always originates from 

 a process or pole or prolongation of a nerve cell. 



Du Bois Reymond mentions that, during his last 

 year of medical study, Helmholtz had an attack of 

 typhus fever, for which he was treated gratuitously 

 in the hospital, while his small weekly allowance for 

 board was continued. At the end of his illness 

 Helmholtz found himself in possession of a little : 

 fund. This was expended in the purchase of the ' 

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