1 30 Traces of Unity in 



traction is accompanied by an electrical discharge- 

 analogous to that of the torpedo. And as for M. Du 

 Bois-Reymond,* it may be said that he has demon- 

 trated most conclusively that there are electrical cur- 

 rents in nerve in brain, spinal cord, and other great 

 nerve-centres, in sensory, motor, and mixed nerves, in 

 the minutest fragment as well as in masses of consider- 

 able size, that the electrical current of muscle, which 

 had been already discovered by Matteucci, may be 

 traced from the entire muscle to the single primitive 

 fasciculus, that Nobili's ' frog-current,' instead of 

 being peculiar to the frog, is nothing more than the out- 

 flowing of the currents from the muscles and nerves, 

 that the law of the current of the muscle in the frog 

 is the same as that of the current of muscle in man, rab- 

 bits, guinea-pigs and mice, in pigeons and sparrows, in 

 tortoises, lizards, adders, toads, tadpoles, and salamanders, 

 in tench, in freshwater crabs, in glow-worms, in earth- 

 worms in creatures belonging to every department ~of 

 the animal kingdom, that the law of the current in 

 muscle agrees in every particular with the law of the 

 current in nerve, and also with that of the feeble cur- 

 rents that are met with in tendon and other living 

 tissues, and that there are sundry changes in the current 

 of muscle and nerve under certain circumstances, as 

 during muscular contraction, during nervous action, 

 under the influence of continuous and interrupted voltaic 

 currents, and so on, which changes, as I shall hope to- 

 show in due time, are of fundamental importance in- 

 clearing up much that would otherwise be impenetrable 

 darkness in the physiology of muscular action and sen- 

 sation. 



Before the discovery of the galvanometer the atten- 



* " Untersuchungen Uher thierische Electricitat. " Berlin. 1849, 1853. 



