Thomas Andrews to Faraday   1 December 1843

Belfast 1st December 1843.

My dear Sir,

Various circumstances have delayed the completion of my paper¹ till the present time. I now send it to you in conformity with your kind permission², and as you have been so good as to promise me your opinion with sincerity I have only the request to make that if after perusing it, you entertain any reasonable doubt of its being published by the R.S. you will frankly say so. I frankly confess to you that I should not like to receive it back as a rejected communication, more particularly as the Irish Transactions have been always within my reach. I hope you will excuse me for writing so boldly, but I am a little sensitive.

As to the subject itself I suppose you are already aware that only three papers have hitherto appeared in connexion with it. One published by myself (which I enclose) in the Irish Transactions³ - another by M. Hess⁴ in Poggendorff's Annalen⁵, of which you will find a translation in the Annales de Chimie 2ème Série, t.75 p.80 and 3ème Serie t.IV, p.211 and p.290⁶; and an abstract in the 19th and 20th vols. of the Philosophical Magazine⁷,- and a third by Mr. Graham in the Memoirs of the Chemical Society⁸. In a recent number of Poggendorff's Annalen Hess has written a reply to a short notice by Graham in the Proceedings of the Chemical Society and to that part of my paper which refers to the absence of heat in the formation of double and acid salts. It is chiefly remarkable for the asperity of its language; he acknowledges that there is no evolution of heat when solutions of the proximate constituents are mixed; but enters into an elaborate argument applicable only to the sulphates to show that my second law is false. To shew you a curious specimen of candid criticism I have literally translated the following passage.

"He (Andrews) thinks that the heat developed depends on the bases, but not on the acids; since it appears to him that one and the same base developes the same [I said nearly the same]⁹ heat with all the acids. To render this conclusion probable to the reader [the deception was a very flimsy one]¹⁰ he first lays aside all the numbers which contain sulphuric acid, then takes the mean of the remainder and shews how much the heat developed by each acid differs from the mean number. He thinks that these differences lie within the limits of the errors of experiment. <cross><cross><cross> He might have at least remarked that certain acids were always +, others -, and that too with all the bases, which could not have happened from chance"<cross>¹¹. Now if you will refer to p.15¹² of my paper you will see that I state that sulphuric acid developes nearly 1˚ more, and the tartaric, citric & succinic acids half a degree less than the mean; and that the differences observed with the other acids are almost within the errors of experiment. My paper was translated into Poggendorff's Ann¹³ verbatim so that Hess must have seen these very observations. The conclusion to which he finally comes is only, as he gently expresses it, that My "second law is false"¹⁴.

I have no intention of taking any notice of observations written in such a spirit, particularly as the experiments detailed in my present communication appear to me finally to settle the question - at least so far as the present state of chemical knowledge enables us to ascertain the reactions.

You will greatly oblige me by directing your attention to the general observations at the commencement of the paper and at p.32 to 38¹⁵; as I may perhaps have omitted the consideration of some essential condition.

I have only again to thank you for your many acts of kindness to me, remaining

Yours most sincerely & obliged | (signed) Thomas Andrews

To | Michael Faraday Esq | &c &c &c

<cross> Poggendorff's Annalen Bd.57, p.483.4 [sic].