64 HERMANN VON HELMHOLTZ 



* the Rate of Transmission of Excitation in Nerve', with the 

 request that he would communicate it to the Physical Society, 

 1 to secure priority in their Proceedings/ He sent the notice 

 at the same time to Johannes Miiller for the Academy in 

 Berlin, and to Alexander von Humboldt for Paris, contenting 

 himself for the moment with the statement of his discovery, 

 that during the excitation of nerve with the current induced in 

 a coil by the opening of the circuit in another coil, a measur- 

 able time (some 0-0014-0-0020 second) elapses, before the 

 stimulus of an instantaneous electrical current applied to 

 the sciatic plexus of large frogs, with nerves 50-60 millimeters 

 in length, is transmitted to the point at which the nerve enters 

 the gastrocnemius muscle. He tells du Bois-Reymond how, 

 'after a severe struggle, I have converted a bold mathemati- 

 cian, who gets somewhat confused over non-mathematical 

 logic, and is himself lecturer on mechanics, to the doctrine of 

 the conservation of energy, so that it is now official doctrine in 

 this University. Neumann is rather difficult to get at; he is 

 hypochondriacal, shy, but a thinker of the first order/ 



Du Bois was again the only man who understood the brief 

 note thus published by Helmholtz merely to establish his 

 priority. 'Your work, I say with pride and grief, is under- 

 stood and recognized in Berlin by myself alone. You really 

 have, begging your pardon, expressed the subject so obscurely 

 that your report could at best only be an introduction to the 

 rediscovery of the method. The consequence was that Miiller 

 failed to rediscover it, and the Academicians decided after he 

 had spoken that you had not eliminated the time lost during 

 the contraction of the muscle. I had to explain it separately to 

 one after the other to Dove, to Magnus, to M tiller himself, 

 who would have nothing to do with it. I brought it forward 

 at the Physical Society, where at any rate we did not have 

 the same difficulty. Humboldt was quite mystified, and 

 refused to send your note to Paris, so I offered to make it 

 plainer. I have done this on my own responsibility ; you will 

 observe that I have not altered a single detail, but kept rigidly 

 to what you gave me, while I have developed it inductively. 

 The note on rapidity per second is not mine, but Humboldt's/ 

 In conclusion du Bois-Reymond expresses his wish that 

 Helmholtz would continue these researches: 'The lay of 



