Faraday to John Tyndall   19 April 1851

Hastings 19th April 1851.

Dear Sir,

Whilst here resting for awhile I take the opportunity of thanking you for your letter of the 4th of February¹ and also for the copy of the paper in the phil. Magazine which I have received². I had read the paper before and was very glad to have the development of your researches more at large than in your letter. Such papers as yours make me feel more than ever the loss of memory I have sustained, for there is no reading them or at least retaining the argument under such a deficiency. Mathematical formulae more than anything requires quickness and surety [in receiving and retaining the true value of the symbols used,]³ and whilst one has to look back at every moment to the beginning of a paper, to see what H or <alpha> or <beta> mean there is no making way. Still though I cannot hold the whole train of reasoning in my mind at once I am fully able to appreciate the value of the results you arrive at, and it appears to me that they are exceedingly well established and of very great consequence. These elementary laws of action are of so much consequence in the development of the nature of a force which, like magnetism is as yet new to us.

My views with regard to the cause of the annual, diurnal, and [some]⁴ other variations are not yet published though printed⁵. The next part of the philosophical transactions will contain them. I am very sorry I am not able to send you a copy from those allowed to me, but I have had so many applications from those who had some degree of right that they are all gone. I only hope that when you see the Transactions you may find reason to think favourably of my hypotheses. Time does not lessen my confidence in the view I have taken but I trust when relieved from my present duties and somewhat stronger in health to add experimental results regarding oxygen so that the mathematicians may be able to take it up.

As you say in the close of your letter I have far more confidence in the one man who works mentally and bodily at a matter than in the six who merely talk about it - and I therefore hope and am fully persuaded that you are working. Nature is our kindest friend and best critic (exciter?)⁶ in experimental science if we only allow her intimations to fall unbiassed on our minds. Nothing is so good as an experiment which whilst it sets an error right gives us a reward for our humility in being refreshed by an absolute advancement in knowledge[.]

I am my dear Sir | your very obliged and faithful Servant | M. Faraday

Dr. J. Tyndall | &c &c