1794

Thomas Beddoes to James Watt, 14 August 1794

Aug^t 14 1794

Dear Sir

I have been considering the most advantageous way of producing oxygene air & making some exp^ts on the subject. Manganese free from calcareous earth such as that from near Exeter with vitriolic acid affords this air in great quantity & of extreme purity. a pound of each will yield 1.1/2 or 2 cubic feet, the heat requisite is rather above what our Argand’s lamp will afford; so a sand heat will be requisite; & I think a sand-pot with a chimney in one piece c^d be adapted to your furnace – to get oxygene air by a dry heat I thought if we c^d contrive to send both air & acid extricated from nitre through red hot pieces of earthen ware we sh^d <at once> free the air from acid & avoid complication of machinery – For this purpose I thought it w^d be sufficient to throw pieces of earthern ware on the nitre in a cast-iron matress – If this will not do, no doubt sp. of nitre will yield air free from acid & of unexceptionable purity – I was recommended to an engraver here, but do not like his workmanship; hence I have still the drawings by me, They w^d have been given to Mr Southall, as you advised but he was from home. I therefore waited till your return, in order to know whether the above addition of a sand-pot is practicable & has your approbation, supposing in this case that either another plate will be necessary, or another figure to the drawings already done – [Xxxx] I shall now only beg your opinion on this point & then with^t further delay expedite the publication of the pamphlet in which they will be introduced –

I shall mention to some correspondents who have enquired about apparatus, where it may be had – some facts tending to shew the virtues of oxygen air have been transmitted to me, particularly a case of chlorosis, where its effects were very decisive. I am going to give it in such a case myself –

a proof of my proposals was left at Soho – I hope you will find the [manner] particulars unexceptionable. They w^d have been published but it is, it seems, a necessary formality to nominate trustees for the money. For this purpose I applied to 4 or 5 monied men of known responsibility, one of whom, whose name I wish for most, has kept me waiting for his answer longer than he ought – I have received from Mr Tho^s Wedgwood a very friendly & encouraging letter relative to this project.

I am Dear Sir,
with perfect good wishes to yourself & Mrs Watt
yours

Tho^s Beddoes

Address: James Watt Esq / Heathfield / Birmingham
Endorsement: Dr Beddoes / Aug^t 14^th / 1794
MS: LoB MS 3219/4/28/09