John Tyndall to Faraday   26 January 1853

Queenwood College | near Stockbridge Hants | 26th Jan. 1853.

Dear Prof. Faraday,

Will you allow me to introduce to your notice an experiment I made in Berlin, which I thought very remarkable at the time, but which I have had no opportunity to follow up since. It appears to me to lead to the same conclusion, if it be not the same in principle as those you have recently made. - It proves that the law of decrease for iron is different from that of a salt of the metal. Do you not consider it probable that a difference of this kind between water and bismuth is the cause of the greater repulsion of the latter at an increased distance. As the bismuth is carried to a greater distance it may in fact be regarded as immersed in a new fluid altogether, and if the difference of repulsion between this fluid and the bismuth be greater than the corresponding difference near the poles the facts observed would of course follow.

I confess I never entertained the thought of applying the experiments described on the accompanying leaf as you have done, and though startled by the profound ingenuity of your argument on Friday night¹, I did not imagine that the conclusion could be at all approached by the route chosen, the old magnetic law has still I confess a hold upon my convictions.

Believe me dear Sir | Most faithfully Yours | John Tyndall