To William Francis   15th Oct. 1851

Queenwood 15^th Oct. 1851

Dear Francis.

I went to the station yesterday morning and secured the parcel¹ containing all mentioned in M^r Gyde’s note.² I am much obliged to you for all and now proceed forthwith to Wood’s paper.³

I scarcely know what to say to it – There is manifest cleverness evinced throughout but the subject appears to be hastily handled – If you have patience I will run through a portion of it and dot down the impressions that occur to me.

1. The spelling and grammar will require a little attention. There are some pencils marks, by whom made I know not, but they are too faint to be read.

2. In (14) I would say ‘— instead of a cube of iron we substitute a cube of ice at 0°F.’ The cube of iron was not at 0°F but at 0°C.

3. What is ‘motion abstractedly considered’? (15) his argument here is against heat being the result of motion has, I conceive, no force; it appears to rest upon a misconception.

4⁴. That is a sweeping conclusion at the end of (15). The idea of equilibrium implies a balance of forces. If two bodies are in equilibrium true they remain so until acted on by a third; this destroys the equilibrium – of what? Of forces to be sure; of what forces? ‘not attraction and repulsion saith D^r Woods’⁵; of what then? Subtract these and what remains to be equilibrated?

5. He says in (16) the greater the amount of matter in a given space the more difficult it is to take its particles asunder. Now water contains more matter than ice bulk for bulk, mercury than steel but are the particles of the solid more easily taken asunder than those of the liquid?

6. I’ll leave (19) and (20) to be dealt with by the author of the Vestiges who imagines the sun to have at one time filled the entire space between here and the uttermost planet.⁶

7. We might fasten an argument on almost every paragraph. With regard to (24) it might be urged that 1 vol. of carbon vapour unites without consideration with 1 vol of oxygen, the result

<up to here the source is RDS 27/4; the continuation is from StBPL T&F, Authors’ letters >

being two volumes of carbonic oxide. The combination is accompanied by heat – but there is no approach of atoms –whence comes the heat then?

<8>. If heat by developed by the explosion of chloride of Nitrogen which is certainly exceedingly probable his observations in (26) would fail. That’s a rich illustration in (27) ‘boiling water will scald &c’⁷ –

I think I may stop here as what I have written will impart to you my notion of the paper. It is marked by cleverness but not by the strictness which scientific matters require. [His] mind is wandering about an important subject which I cannot think he has yet mastered. [His] paper may serve to agitate an important question, but my notion is that such articles ought to be introduced sparingly. [This] remark applies, I imagine, with still more force to the paper of Reuben Phillips.⁸ Such theories are more interesting to the finder than to any body else. This clipping and patching up of an old hypothesis is thankless work. [Walloston’s]⁹ theory is at best a make-shift and the filing of it up will not add much to our intellectual comfort. Such notions as those entertained by M^r Phillips may be of a certain practical value to a man in his private investigations but I doubt the wisdom of giving them publicity – you must however take all I say on this subject with great caution – I have seen so many pretty theories which proved pure brain-bubbles that I have conceived a certain prejudice against them.

At the end of (16) of my last paper¹⁰ stands the letter B; ‘the magnetic sphere will move to the pole B’ – could you change this into A for me – If the copies are already struck off it might be mentioned as an erratum. The letter d′ is omitted in fig. I; but this is of little consequence.

most faithfully yours J. Tyndall

When next you have occasion to write to me be good enough to send me Sir John Herschell’s address¹¹

RDS 27/4 and StBPL T&F, Authors’ letters