NERVE-FIBRES AND NERVE-CELLS 121 



same position is illustrated by a story which Dr. Hughlings 

 Jackson told to the Neurological Society in his presidential 

 address. Soon after he had commenced practice, a patient, 

 whose leg had been amputated, sent for him in great dis- 

 tress. " Doctor, do you know what has become of my leg?" 

 "Yes, it is buried in old St. Pancras Churchyard." 

 "Then, for heaven's sake, doctor, have it dug up and 

 scratch it just above the ankle." 



Having shown that the nerve-fibres are incapable of 

 tampering with the messages which they transmit, there 

 remains only the grey matter of the spinal cord and brain. 

 This consists of nerve-cells lying in a plexus or feltwork of 

 filaments derived from the branching of the processes of 

 cells and fibres. This feltwork is of quite inconceivable 

 richness, and it matters little for our present argument 

 whether it be a network in the proper sense of the word 

 whether its filaments are continuous from fibre to cell and 

 vice versa or whether, as is almost universally held at the 

 present moment, they end freely and convey their impulses 

 across from one filament to another filament which lies near 

 to it, perhaps in contact, but not in continuity. At the 

 present time almost all anatomists hold the " Neuron 

 theory." They look upon the elements of nervous tissue as 

 cells, each with one long unbroken process, the nerve-fibre 

 reaching, it may be, from the spinal cord to the hand or 

 foot, and many "protoplasmic" processes which branch; 

 and they consider that every neuron is absolutely uncon- 

 nected with all other neurons. As the writer has persistently 

 opposed this theory since it was first formulated, he had 

 better pass over the question as to the nature of the nerve 

 feltwork in silence. Is it the nerve-cells or the nerve- 

 feltwork which manipulates the messages which pass 

 through the grey matter ? for all impulses pass through it. 

 It is the tissue in which they are redirected from sensory 

 into motor channels. Several hypotheses have recently 

 been started to account for the making and breaking of the 



