72 HERMANN VON HELMHOLTZ 



Two points in this lecture gave rise to an interesting corre- 

 spondence with du Bois-Reymond. Helmholtz, using what 

 is now a familiar figure, compared the nerve-fibres with the 

 wires of the electric telegraph, which in an instant transmit 

 intelligence from the outposts to the controlling centre, and 

 then convey its orders back to the outlying parts to be executed 

 there; and at the close of his discourse he illustrated the 

 rapidity of nervous conduction by saying that the whale 

 probably feels a wound near its tail in about one second, and 

 requires another second to send back orders to the tail to 

 defend itself. On March 18, 1851, du Bois sends Helmholtz 

 a lecture which he had given at the Sing-Akademie before 

 the ' familiar audience of non-working classes ', and remarks : 

 'Your surprise on reading this will be little less than my 

 own on reading your lecture. Apparently we have hit on the 

 same thing in two illustrations, and in various other points, 

 even to the expressions we make use of, so that no stranger 

 would absolve me from plagiarism. I feel greatly flattered 

 at this conformity in the motions of our brain molecules. Give 

 my lecture to your good wife to read. The ladies are angry 

 because I made myself comprehensible to them what do I 

 take them for ? they expected something more scientific from 

 me/ He then describes the difficulty he finds in devising an 

 instrument which shall be set going by a muscle so as to close 

 the circuit during a given fraction of the twitch, and ends with 

 the words : ' Write and tell me what avalanche of ideas this 

 tinkling of a mule-bell rouses in your brain/ After congratu- 

 lating du Bois in his answer of April n on his election to 

 the full membership of the Academy, Helmholtz replies : 



'As regards the coincidence in our lectures I concede you 

 priority in the matter of the electric telegraph, since you long 

 ago suggested the hypothesis that the ganglia represent the 

 intermediate stations of the electric telegraph in the nerve 

 circuit. But in the story of the whale the truth is so romantic 

 that no one will believe it. The moral is that people can easily 

 be mistaken about plagiarism. . . . My wife joins forces with 

 those who say that you have made yourself too intelligible. 

 It is impossible to please every one on these occasions, but 

 one generally gets more thanks for not making one's stuff too 

 plain to the audience, and for leaving the majority a few 



