Faraday to Henry Wentworth Acland   18 October 1850

Royal Institution | 18 Octr. 1850

My dear Sir

I had your letter¹ this morning and am able to say very little that will be satisfactory to you in respect of observations of the Electric & Magnetic condition of the atmosphere. You know the difference between the theorist & the observer & I have been very little of the observer in these matters. This I know that careless or slight observations are of no value & that to make good ones the most perfect apparatus & some practice in observing is needful[.] Mr. Ronalds² of the Kew Observatory would be able & I have no doubt happy to tell you all that can be communicated from one to another & could assist you much in that respect[.]

Your letter in some degree jumps with my present pursuits for I have been hard at work on a branch of Science which I have called atmospheric magnetism[.] Only to think of oxygen as a highly magnetic body carrying all its properties in that respect into the atmosphere[.] At common temperatures it is as magnetic as a solution containing 17 times its weight of proto sulphate of iron i.e equal bulks of oxygen & of such solutions have equal magnetic powers. Besides all that there is this beautiful fact[.] As iron at a certain high temperature & Nickel at the heat of boiling oil lose their magnetic forces in part not entirely, so oxygen by heat loses of its magnetic power & natural temperatures occur at that point or within that range which affects the oxygen & hence as I think I shew the greater number of variation of terrestrial magnetism, the annual & diurnal variations &c & a multitude of accidental variations which the photographic registrations shew[.] My papers³ are already at the RS & in the hands of Mr. Christie & Coll Sabine & you will very shortly hear of them[.]

Ever My dear Sir | Most Truly Yours | M. Faraday

Dr Ackland [sic] | &c &c