Heidelberg 5.1.61
Verehrter Freund
in der Vorraussetzung, dass Sie irgend ein Mal die bevorstehende große Industrie Austellung besuchen werden, möchte ich Sie bitten, dabei gelegentlich ein Exemplar des von mir construierten Myographion ansehen zu wollen, welches einer unserer geschicktesten Mechaniker, Herr Fessel aus Coeln zur Ausstellung schicken will, und nachzusehen, ob es wohl richtig zusammengesetzt und aufgestellt ist. Es ist das Instrument bestimmt Zuckungen eines Muskels auf einen rotierenden kleinen Glascylinder aufzuschreiben. Ein kurzer Bericht über die damit angestellten Versuche, die namentlich auch Messung der Fortpflanzungsgeschwingigkeit der Reizung in den Nerven bezweckten, ist einmal im Philosophical Magazine, vielleicht von Ihnen selbst gegeben worden. Herr Fessel fürchtet, daß bei der Zusammensetzung des Apparats Missverständnisse unterlaufen möchten, und hat mich deshalb gebeten einem meiner Londoner Freunde diese Bitte vorzulegen.
Mit den besten Grüßen | Ihr H. Helmholtz
Heidelberg 5.1.61
Dear Friend
Assuming that you will visit the forthcoming great Exhibition of Industry2 at some point, I would like to ask you at some point to look at the example of the myographion3 built by me, which one of our most skillful mechanics, Mr Fessel4 from Cologne, will send to the Exhibition, and see if it is properly put together and exhibited. The instrument is for recording the contractions of a muscle onto a small rotating glass cylinder. A short report on the experiments conducted with it, which aimed at measuring the speed of transmission of nerve impulses, appeared in the Philosophical Magazine, perhaps arranged by yourself.5 Mr Fessel fears that there might be misunderstandings regarding the assembly of the apparatus, and has therefore asked me to put this request to one of my London friends.
With the best greetings | Your H. Helmholtz
RI MS JT/1/H/40
[1 May 1862]: The letter appears to give a date of 5 January 1861, but the context of the Exhibition of Industry implies 1862. Letter 1890 appears to be the reply, making 1 May 1862 a possible date for this request. Helmholtz normally wrote the day before the month, but 1 May is more likely than 5 January for this letter.
great Exhibition of Industry: the 1862 International Exhibition was held in London from 1 May to 1 November 1862.
myographion: Helmholtz’s myographion, invented in 1852, was a device that allowed the contraction of a muscle to be traced on a rotating drum.
Mr Fessel: Friedrich Fessel.
appeared in the Philosophical Magazine, perhaps arranged by yourself: Helmholtz described his experimental method in H. Helmholtz, ‘On the Methods of Measuring very Small Portions of Time, and their application to Physiological Purposes’, Phil. Mag., 6 (1853), pp. 313–25, though he describes the instrument as made by M. E. Rekoss. Tyndall ‘communicated’ the paper (* on p. 313).
Please cite as “Tyndall1890,” in Ɛpsilon: The John Tyndall Collection accessed on