176 Correspondence on the Preservation of Timber. 



made about two years ago to this department, by Mr. Jos. Jones of Amlwch, 

 I have their Lordships' commands to acquaint you that they have no know- 

 ledge of the publication you allude to. 1 am, Sir, your humble servant, 



John Barrow." 



Mr. Sanderson then wrote to Mr. Barrow as follows : — 



" Plas Newydd, Sept. 28. 1820. 



" Sir, — I beg to acknowledge the receipt of your letter of the 22d instant, 

 in which you are pleased to acquaint me, in reply to mine of the 20th, that 

 the Lords Commissioners of the Admiralty have no knowledge of the publi- 

 cation alluded to. I did not for one moment suppose that their Lordships 

 would give their sanction to a publication of matter drawn from private 

 correspondence of Mr. Croker ; indeed, my allusion to that publication was 

 merely incidental. It was the chief object of my letter to ascertain whether 

 Mr. Jones's statement of facts relative to the preservation of timber had 

 received the consideration of the Lords Commissioners of the Admiralty, or 

 of the Commissioners of the Navy ; and I hope I may now, without impro- 

 priety, enquire whether any and what report has been made upon it ? I should 

 also feel much obliged if you would have the goodness to procure for me the 

 return of Mr. Jones's letter, as I did not keep a copy. I have the honour to 

 be, Sir, your most obedient Servant, John Sanderson. 



" To John Barrow, Esq." 



To which the following final reply was given by Mr. Barrow : — 



" Admiralty Office, 30th Sept., 1820. 



" Sir, — Having laid before the Lords Commissioners of the Admiralty your 

 letter of the 28th instant, enquiring whether any report was made on Mr. 

 Jones's letter of the 20th of October, 1817, respecting a plan for the preserva- 

 tion of timber, and requesting that Mr. Jones's letter may be returned to you, 

 I have it in command to acquaint you that the letter in question cannot be 

 returned to you ; and that, from a report made by the Navy Board on the 

 subject, their Lordships did not mean to give Mr. Jones any further trouble 

 on the matter. I am, Sir, your very humble Servant, John Barrow. 



" To Mr. John Sanderson, Plas Newydd, Anglesea." 



" The following observations and experiments were made by me in January, 

 1818, on the chemical properties of the mineral water of Parys Mountain, 

 by which timber is preserved : — This water is known to contain copper and 

 iron, held in solution by sulphuric acid. ' Wood, when distilled in a retort, 

 yields an acid liquor of a peculiar taste and smell and distinguished by the 

 name of pyroligneous, and formerly considered as a distinct acid, but it is now 

 ascertained that it is merely the acetic acid, combined with an empyreumatic 

 oil.' — Thompson. 



" I obtained from a manufacturer in Liverpool some pyroligneous acid in its 

 simplest state, for the purpose of making experiments. On adding an equal 

 quantity of sulphuric acid to the pyroligneous, it was speedily decomposed, 

 and a black substance was precipitated, which, when dried, appeared to be 

 carbon. A small quantity of sulphuric acid being applied, changed the colour 

 to a dark, and nearly black. The Parys Mountain water being added to an 

 equal portion of pyroligneous acid, changed its colour precisely the same as 

 in the last experiment, when sulphuric acid was used alone. 



" Is the sulphuric acid contained in the water, under any circumstances, suffi- 

 ciently strong to carbonise the sap within the pores of the wood ? I am 

 persuaded it does convert some part of the sap of timber into charcoal ; and 

 when it is properly saturated, every pore becomes lined with the substance, 

 which, when once formed, is afterwards insoluble in water ; thus making use 

 of the otherwise destructive sap to char the wood ; charring the surface of 

 wood having always been considered a preservative of timber from dry rot. 



" Caernarvon, Sept. 9. 1835. Joseph Jones." 





