FUNDAMENTAL "LAWS" OF NERVE-ACTION. 187 



direction and propagation of nervous impulses. The cell 

 of Golgi and Cajal bore no functional interpretation other 

 or more precise than was already placed upon the cell of 

 Deiters ; in either case the distinction between nervous and 

 protoplasmic processes appeared to be equally gratuitous ; 

 and as regards the formation of elementary notions, the 

 collateral branches of axis-cylinder processes and the dis- 

 continuity of fibrous network and nerve - cell, however 

 significant these facts might some day prove to be in 

 relation to the transmission and diffusion of nerve-impulses, 

 were for the moment obstructive rather than auxiliary. 



The anatomical descriptions of collaterals were obviously 

 selected under the guiding influence of physiological con- 

 siderations. Those of pericellular networks simply signified 

 to us that continuity of structure was not indispensable 

 to propagation of nerve-impulses. Collaterals were pointed 

 to as the distinct continuous paths by whose presence we 

 might understand the manifold radiations of nerve-impulses. 

 On the other hand, arborisations of fibrils, their want of 

 protoplasmic continuity with cells and with each other, 

 instructed us to regard continuity of protoplasm as an un- 

 essential condition of nerve conduction. 



Therefore it was that while introducing 1 into lectures 

 such knowledge as I possessed concerning the then newer 

 histological developments associated with the names of 

 Golgi, Cajal, Retzius, I deliberately omitted from a written 

 introduction to physiology any detailed description of ana- 

 tomical facts to which no -plausible functional significance 

 could be reasonably assigned. The omission of such well- 

 known and important facts was criticised by more than one 

 of my friends, without, however, adding to my knowledge 

 more than that it was inexpedient to omit mention of such 

 remarkable researches. 



I held, and hold, that it is inexpedient to prematurely 

 introduce into elementary teaching the latest "discovery" 

 in physiology and a fortiori in histology. Yet so far from 

 ignoring these particular researches, they had been an 

 object of my frequent consideration and speculation. And 

 that to such an extent that the speculation took precise 



