PHYSICAL SCIENCE AND ITS CONNECTIONS. 7 



connected with physical diffusion, and with the physical 

 theories of the constitution of matter, they may rightly be 

 noticed as on the connecting road between physics and 

 chemistry. In this same connection it is interesting to 

 consider the way in which electrolysis alters diffusion. 

 Both in gases and liquids it appears as if the ions were 

 carried by an electric current through metallic plates. It 

 has been observed that the negative glow can penetrate thin 

 metallic plates even into the air outside the exhausted tube. 

 This certainly looks as if the ions were able, with the 

 assistance of the electric current, to pass through the metal. 

 It has also been found that electrolysis in liquids can take 

 place through a thin metallic plate while a thick one has the 

 electrolytic ions deposited on its surface or actively attacking 

 its substance. If metallic plates can act so there seems 

 every reason to expect that other diaphragms may act 

 similarly. It appears as if electrolysis can be forced 

 through a very short metallic layer. As if Grothus chains 

 of metal and ion can hand on the ions for a short distance 

 into the metal, but that ordinary metallic conduction rapidly 

 sets in. This would all lend support to the theory that 

 ordinary metallic conduction is a disorganised kind of 

 electrolysis ; disorganised by a rapid diffusion which re- 

 stores the bonds as rapidly as they are broken down by 

 the electrolysis, so that no continuous vection takes place, 

 except as it would now appear through a very short 

 distance. That organic membranes can do something akin 

 to conduct metallically seems certain from the possibility of 

 accumulating a high electric pressure by means of numerous 

 cells in electrical fishes. By merely repeating a number of 

 liquid contacts through porous diaphragms it is not possible 

 to accumulate a high electric pressure. It seems as if some 

 unstable body were set free by the nervous stimulus which 

 probably diffuses through some septum, producing thereby 

 an electric pressure, which may be transmitted by some 

 means akin to conduction to the next cell. It may be, of 

 course, that this diffusion through the cell wall is what is 

 akin to conduction, and that the electrolysis is what takes 

 place through the other septum. It must, however, also be 



