James

May 24/60

I beg to ack^ge the rec^t of y^r l^r of the yest^y – I will begin by advert^g You say, that it w^d be of use t you if I can show how maps of the size y mentⁿ can be accur^ly & econom^ly engrav^d by the ph^c prss – If I rightly underst^d y^r mean^g y. w^d engrave on 1 sheet, 16 sheets each of th size of 9 x 4 inches. This w^d make 1 sheet of the size of 36 x 16 inches I have not yet attempt^d so large an engrav^g but I do not see any partic^r diffic^ty in the way – Suppos^g tht I had at my disposal the resources of a large Gov^t establ^t (as you w^d have) then I think that the engraving w^d be effected in a satisf^y manner.

As to accuracy you can judge f^m the small specimen maps I sent you whthr th process is accurate.

You will make allow^ce of course for the clumsy my own very imperfect manipulatⁿ, & view the process as it w^d be if carried out carefully by persons artists of talent employed by Govern^t

As to economy th process may be S^d lit^lly to cost nothing, except the expence of the copper or steel plate employ^d –

I presume that casual blemishes c^d be removed without diffic^ly by a skilful engraver – he w^d b I think that 99-100^ths of th Map w^d be without blemish, & of course the process can be further improvd. As my pat^t to w^ch I alluded in my last l^r None of the facts you mentⁿ are at all new to us We went thro’ th whole of them in /56 whn they were produced before a judge at Chambers – I do not claim the to be the inventor first who used Bich P. in photgry – such a claim w^d be invalid, it was known for sev^l y^rs before /52 & no one c^d turn it to a useful process, in fact it was nearly forgotten; – my claim is for the emplymt of in phot^y of a mixture of bich ph with gum or its equivalents gelatin &c – as clearly stated in my specfⁿ – let any one omit the latter subst^ces & I have nothing to object ag^st him? – It is like The introductⁿ of the gum renders a new class of useful processes possible, w^ch is a good test of a real practical inventⁿ

The last inv^ter of Many of the most impor^t pat^s on record are simply for the combinⁿ of 2 invent^ns both of w^ch are perfectly well known but had not bⁿ combind before. For such a pat^t to be valid it is held, that the result of product or manufacture must be finally new w^ch w^d not result f^m either process separat^ly

Such a pat^t is valid, even when the result of the process or manuf^re is the same as before ( except anything tho’ perhaps better & cheaper)

But, w^th resp^t t wht y say abt M^r Carpmael (<illegible>) I cannot help think^g tht some great mistake must hve occurrd to For tht gentⁿ is a <illegible> fn^d of mine, I have consulted him repeatedly ab^t this v^y matter & I can assure y. tht his opinⁿ is the <<illegible>> of what you will attribute mention to him If you doubt it – are you willing to leave the questⁿ to M^r W. Cs arbitratⁿ? (As I believe)

before him – If you doubt it but that he w^d be of this a v^y diff^nt opinⁿ to what y. think remark If you doubt it

As I believe the Ordn^ce acc^ts are public, w^d it be an indiscreet questⁿ if I were to ask what is the expence to Gov^t of simply engraving the Ord^ce map of 36 x 16 inches – I wish to know see wh^r it w^d be worth while to incur any add^l expence in perfecting my ph^c pss for that purpose & <once?> of course by employing talented assistants to do superint^d it

better & cheaper] & à futiori it is valid when the resulting process is somethg new (as for inst^ce on a steel Engraving, inst^d of a paper-phtogrph)

I am a good deal surprised at wh^t y. say ab^t M^r W^m Carpmael – But I cannot half think^g tht some g^t mistake must h. occurred – I have a high respect for M^r Carpmael, & – I do not think that such can w^d be his opinⁿ if wh if all the facts are were placed before

James/

May 24, 1860

I beg to acknowledge the receipt of your letter of the yesterday – I will begin by adverting You say, that it would be of use to you if I can show how maps of the size you mention can be accurately and economically engraved by the photoglyphic process – If I rightly understand your meaning you would engrave on one sheet, sixteen sheets each of the size of nine by four inches. This would make one sheet of the size of thirty-six by sixteen inches I have not yet attempted so large an engraving but I do not see any particular difficulty in the way – Supposing that I had at my disposal the resources of a large Government establishment (as you would have) then I think that the engraving would be effected in a satisfactory manner.

As to accuracy you can judge from the small specimen maps I sent you whether the process is accurate. You will make allowance of course for the clumsy my own very imperfect manipulation, and view the process as it would be if carried out carefully by <persons> <artists> of talent employed by Government. As to economy the process may be said literally to cost nothing, except the expence of the copper or steel plate employed –

I presume that casual blemishes could be removed without difficulty by a skilful engraver – he would be I think that ninety-nine one-hundredths of the Map would be without blemish, and of course the process can be further improved. As to my patent to which I alluded in my last letter, none of the facts you mention are at all new to us, we went through the whole of them in 1856 when they were produced before a judge at Chambers – I do not claim the to be the inventor first who used Bichromate of Potash in photography – such a claim would be invalid, it was known for several years before 1852, and no one could turn it to a useful process, in fact it was nearly forgotten; – my claim is for the employment of in photography of a mixture of bichromate of potash with gum or its equivalents gelatin etc. – as clearly stated in my specification – let any one omit the latter substances and I have nothing to object against him? – It is like The introduction of the gum renders a new class of useful processes possible, which is a good test of a real practical invention.

The last inventor of Many of the most important patents on record are simply for the combination of two inventions both of which are perfectly well known but had not been combined before. For such a patent to be valid it is held, that the result of product or manufacture must be finally new which would not result from either process separately. Such a patent is valid, even when the result of the process or manufacture is the same as before ( except anything though perhaps better – and cheaper) and à futiori it is valid when the resulting process is something new (as for instance on a steel Engraving, instead of a paper-photograph)

I am a good deal surprised at what you say about M^r William Carpmael ^<1> – But I cannot help thinking that some great mistake must have occurred – I have a high respect for M^r Carpmael, and – I do not think that such can would be his opinion if which if all the facts are were placed before him – If you doubt it but that he would be of the a very different opinion to what you think.

But, with respect to what you say about M^r Carpmael who I cannot help thinking that some great mistake must have occurred to For that gentleman is a <illegible deletion> friend of mine, I have consulted him repeatedly about this very matter and I can assure you that his opinion? is the reverse of what you attribute mention to him If you doubt it – are you willing to leave the question to M^r William Carpmael’s arbitration? If you doubt it As I believe the Ordnance accounts are public, would it be an indiscreet question if I were to ask what is the expence to Government of simply engraving the Ordnance map of thirty-six by sixteen inches – I wish to know see whether it would be worth while to incur any additional expence in perfecting my photographic process for that purpose and once of course by employing talented assistants to do superintend it.

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Notes:

1. William Carpmael (1804–1867), patent agent & engineer, London.