My dear Frankland
If you tell me how I am to send the instrument1 to Mr Lenoir2 I will avail myself of his offer.3 in its present state it will not work. It was certainly too great a risque to send it off without previous trial – The workmanship is superior, and expected to be able to use the instrument in my last lecture but one when I spoke of the law of Ohm,4 but when I came to buy it I found it would not help me.
It would give me great pleasure indeed to spend a week with you among the lakes5 – so much pleasure indeed that I think I should make a great heave to accomplish it. Whether it is possible or not I do not yet know – I am going over to Normandy in a few days when the memory of our trip to Havre6 will be revived.
Ever Yours | John Tyndall
JRL Frankland, 202
the instrument: probably the Pachytrop(e), which could be used to demonstrate Ohm’s Law; see letter 1062, n. 2.
Mr Lenoir: see letter 1062, n. 1.
his offer: presumably to repair the instrument.
my last lecture but one when I spoke of the law of Ohm: Tyndall’s lecture on 29 May was concerned with the electric telegraph and the use of an electrical signalling device that could track the progress of a railway train. The short account of Tyndall’s lecture published in the London Daily News, 30 May 1855, p. 2, makes no mention of Ohm’s Law. ‘The law of Ohm, which is applicable under all circumstances, fully expresses the great fact:– the intensity of an electric current, when a battery is in action, is directly as the whole electromotive force in operation, and inversely as the sum of all the impediments to conduction’ (R. Hunt, Elementary Physics, an Introduction to the Study of Natural Philosophy (London: Reeve & Benham, 1851), p. 256).
among the lakes: in the Lake District. Frankland had purchased a cottage in Windermere; see letter 1073.
memory of our trip to Havre: in June 1848.
Please cite as “Tyndall1093,” in Ɛpsilon: The John Tyndall Collection accessed on