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Document number: 5181
Date: 05 Feb 1845
Recipient: TALBOT William Henry Fox
Author: COOPER John, jnr
Collection: British Library, London, Manuscripts - Fox Talbot Collection
Last updated: 20th December 2015

Trowbridge Febr 5th 1845

Respected Sir/

I hope you will excuse the Liberty I have now taken in addressing you Being a perfect stranger, but feeling assured that you will be interested in any new invention calculated to be beneficial to mankind emboldens me to do so – In the year 1805 then a very young man I introduced the first Steam engine into this Town indeed it was the first in the County – I had the pleasure of purchasing it personally of the late Mathew [sic] Bolton at Soho and of spending a day with him at that place. Finding Steam power very expensive (at that time more so than now) my mind was often engaged with the desirableness of finding a substitute – but business – a very large family and other engagements – prevented my attention to so desirable an object.

About five years ago I was confined to my room for a long time by illness when the subject again engaged my attention which was first turned to Atmospherick pressure as now used on the Rail way – but the difficulty of keeping the continuous valve airtight together with the fixed Steam Engines necessary for the exhaustion of the valve presented themselves the one being difficult the other expensive and therefore the plan was not the one I considered exactly desirable – I then turned my attention to the possibility of obtaining a rotary motion from the same power Atmospherick pressure – but the pressure of [illegible] being equal in all directions proved a [illegible], after trying 40 or 50 different plans I believe I have succeeded in obtaining pressure in one direction only that is I have pressure on the machine in one direction – the reaction being against the Atmosphere itself – the base of both being the same in inches of course the pressure of the reacting base will be from 14 Lb to 15 Lb per inch, on the acting base I should only use from 7 Lb to 8 Lb per inch and that force may be either water or rarified air to that extent, by a simple contrivance I can enlarge the reacting base to any extent and then can apply to the same acting base a greater pressure of either water or condensed air – I am not aware that I have any movement contrary to nature or any known and given law – having a large family 12 living out of 20 my means will not allow my taking out patents from my own resources and to make or have made a working model some former circumstances prove to me would be attended with danger– <1> I could have all necessary assistance from my relations who are the Messrs Hancock and Salter and other friends if I could obtain the favourable opinion of one or two Scientific men – they themselves being quite ignorant of such things and an inventors opinion only cannot be relied upon

The present is to ask you as a favour if you could with conscience give me a short interview and examine my plan – I could attend you at any time or place for that purpose – I beg to add that altho if I can convince friends would at amply supply me with the needful I [text hidden under seal] under an obligation or have made any arrangements with [text hidden under seal] for that purpose

Your reply will much oblige Yours very respectfully
Jno Cooper

Please address
Jno Cooper
Duke Street

[address panel:]
W H Fox Talbot Esqr
Lacock Abbey



1. The Trowbridge clothing firm of John Cooper, snr. and John Cooper, jnr. was declared bankrupt in 1826.