Faraday to Justus von Liebig   5 February 1845

Royal Institution | 5 Feby 1845

My dear Liebig

Your very kind letter¹ was to me a source of the highest gratification & pride and I should long since have answered it (aye even the next day) but that I was continually hoping for some great result such as the condensation of hydrogen or nitrogen or at least oxygen and wanted to send you the first word. But to this time notwithstanding all my labour & continued repet[it]ion of experiments with increased care I have been disappointed. Still I am not cast down & though I have become at last very tired & moreover have an attack of rheumatic influenza - and must for the present rest - yet I trust hereafter to succeed. So my letter will be much poorer in scientific value than I wished - but not my dear friend in the heartiest feelings of affection for your kind expressions which I have by personal knowledge of you learnt to know come from the heart[.]

My wife often speaks of you and I think has more pleasure in her remembrances thoughts & knowledge of you than of any other amongst scientific men with whom she has become acquainted. Your german feelings of home and wife and other subjects are very congenial to her mind & before she went out knowing that I intended writing to you she desired to be most sincerely remembered to you with many thanks for your good opinion. She thinks you flatter her but I tell her you do not. Talking of my wife reminds me of yours whom you join with yourself in persuading us to come & see you at Giessen[.] Tell Mrs. Liebig that I shape out to myself in fancy such a thing though I hardly hope to see it fulfilled and that I please myself with imagining all about you two, and how much she is like you in feeling and the pleasure that I could have in being at home with you & her & chatting altogether just as we do here in our happiest moments and as you & me have done together - but let it pass. I must put such thoughts aside for the present - and the reality perhaps for ever. Nevertheless be assured that if things were to shape themselves I would thank you both for your kind invitation by shewing ourselves at your door[.]

As to my gas experiments I am still working at them and hope the next time I try I shall have oxygen perhaps the end of this week. Olefiant gas, Phosphuretted hydrogen Hydriodic acid, Hydrobromic acid Fluosilicon & Fluoboric have given way & become liquids and Hydriodic and Hydrobromic acids with Ammonia - Sulphuretted hydrogen - Nitrous oxide - Euchlorine - and dry sulphurous acid have become solids. In working at the tensions of the vapours of these bodies I have been much troubled by irregularities which I can only account for by supposing that they are not always as pure as is supposed. Thus both Olefiant gas & Nitrous oxide gas when condensed give me liquids which must be mixtures of at least two substances of different volatility - and in Olefiant gas the mixture appears to be in very different proportions at different times of preparation as if an alteration in the temperature or in the quantities of materials made alterations in the proportions of the different bodies produced. But I have not yet had time to work this out any further than to its effect in causing great differences in the tension of the vapour produced by the condensed liquid obtained at different times. You know that though I may seem lively enough at times that I soon tire and this with a bad memory soon puts an end to my working for a time[.] Adieu my dear Liebig. That blessings may be on you & yours is the earnest wish of your faithful friend

M. Faraday

Address: Dr. Justus Liebig | Professor | &c &c &c &c | University | Giessen | Germany