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THE PHOTOGRAPHIC NEWS. 447 In this way, a print in black, and a sort of dirty white, may be [produced ; after which it is probable that immersion in an alkaline solution may clear up the lights sumiciently. This was the direction in which we were experi menting a few weeks ago, when some matters interfered to prevent our carying the experiments any further. About two months after the publication of the above article, I received by post, from one of the subscribers to the Notes, Mr. John Bouncy, of Dorchester, several prints, which ho assured me were veritably printed in carbon, by the direct action of light upon the paper. These prints were clean in the lights and very promising in general effect, although the pro cess was then far from perfect. Mr. Sutton then proceeds to narrate the details of Mr. Pounce’s first carbon process, of its publication, and the sum of £80 presented to Mr. Pouncy by subscription. He then adds :— The publication of Mr. Bouncy’s process made a great stir among photographers both in France and England; but although it was tried and abandoned by most persons as incomplete, still the possibility of producing a carbon print in this way having been practically demonstrated, several enterprising and intelli gent experimentors took it up as the basis of various modifica tions which have since been largely applied to useful purposes. The names of Asser, Salmon, and Garnier, Joubert, Sir Henry Janies, Mr. Osborne, M. Fargier, and some others, will be familiar to most readers of this work, as the inventors of various modified processes in which carbon forms the material of the photographic reproduction. We may remark, before proceeding further, that Mr. Sutton omits, in the resume we have quoted, to mention the name of M. Becquerel, who, in 1840, experimented largely with the combinations of bichromates and organic matter. Nor does he do entire justice, we conceive, to M. Poitevin and M. Beauregard, in both of whose processes the elements of carbon processes are very distinctly enounced; whether either of them did or did not ever produce pictures by these processes, we are not in a position to state. But still more unfair than this is it, we conceive, to refer to the processes of Joubert, Asser, Osborne, James, and others, as modifications of Mr. Pouncy's process, seeing that they bear no more rela tion to it than they do to Poitevin's, propounded years before. M. Poitevin's specification did, indeed, include a system of photolithography, and whether it ever were reduced to practice or not, his was undoubtedly the first published genn of the application of Mungo Ponton’s discovery to photo lithography. Other experimentalists, amongst whom we may mention our present contributor, Mr. Joseph Lewis, had been working in a similar direction but had not pub lished. The independent discoveries of Asser, Osborne and James respectively of the transfer process, constitute a definite and distinct landmark in the history of this branch of photography. These gentlemen had each profited, doubtless..by the labours and discoveries of those who had preceded them, of Ponton, Becquerel, Talbot, Poitevin, and, possibly, of Mr. Pouncy ; but it appears to us as unfair to describe the processes of these gentlemen as merely modifi cations of Mr Pouncy’s process as it would bo to describe his as simply an imitation of M. Poitevin's. Let us be distinctly understood. We do not wish to deprive Mr. Pouncy of a tittle of his just reward or credit. We have, very ungrudgingly, and we think heartily, ac knowledged the merit of his latest process. We have accorded to him the credit of a hard-working, persevering, and ingenious experimentalist. We did not begrudge him one farthing of the £80 by which his first labours were acknowledged. We hope lie will receive still more sub stantial reward for bis more recent efforts. But we depre cate, on his own behalf, as well as on behalf of other photo graphic inventors and the photographicpublic at large,undue and over-comprehensive claims on his own behalf, because such claims produce a recoil in the public mind, which will prevent him receiving the full justice which would other wise be readily accorded. Mr. Sutton is a warm, generous, and enthusiastic advocate, who is, by his enthusiasm, led to make claims which cannot, we think, be supported, and are scarcely judicious. The question of Mr. [Pouncy’s treatment by the Photo graphic Society is freely handled in the pamphlet, and in a tone far from complimentary to the society. We do not care to discuss the matter now, beyond remarking that a body of men acting without premeditation or concert, rarely do intentional injustice; and that, if Mr. Pouncy received less than justice from the society, an injudicious mode of introducing his discovery was in some degree chargeable for the reception it met. The perfection of all processes in photography has been attained by slight steps, and the contributed suggestions of many persons. This is not less true of carbon processes and photolithographic processes than of other branches. Never theless, Mr. Pouncy’s is a distinct advance, not less the result of a happy ingenuity than of careful experiment. Mr. Sutton refers the first use of asphaltum to Nicephore Niepce, and reminds his readers that he (Mr. Sutton) was the first to experiment and publish results with the use of a greasy ink, results which probably suggested the transfer processes of Asser, Osborne and James. He adds : But no one, to the best of my knowledge, had ever used a mixture of asphaltum and printer’s ink as a sensitive coating applied to paper, before Mr. Pouncy employed it in that way, and to him is due the whole merit of utilizing this mixture in the manner described in his patent. In this respect he has proved that he is something more than the mere industrious worker out of other men’s ideas; and that he is truly an inventor and pioneer, as ingenious in resources as he is indefatigable in experiment. We believe Mr. Sutton is right, although it is quite possible that we shall learn ere long that asphaltum played a part in the pictures of Watt, or Bolton, or Wedgwood. The nearest approximation to Mr. Pouncy’s mixture is to be found in Mr. Gibbon’s process described before the Glasgow Society on the 7th of last January, by Mr. Mactear. In this method, copal varnish, linseed oil, Brunswick black, mastic varnish, and turpentine,—all elements of printing or transfer ink—are combined with bicromate of potash. This mixture is, h wcver, for application to a lithographic stone, and not to paper for producing a proof direct from a negative, as in Mr. Pouncy’s ingenious process. Mr. Sutton, in describing the process, practically ignores the use of bichromate of potash, using asphaltum as the sensitive agent, remarking in another place that it is doubtful whether the addition of the former is attended with an good effect. Mr. Pouncy expressed his regret to us that its insolubility prevented him from adding a larger proportion than he did, as the paper would be much more sensitive if more could be added. We then suggested, as a method of adding more, that it should be dissolved in a very small quantity of water, and by the aid of an alkali combined with the greasy ink. Since then we have tried the experi ment, and have thus combined bichromate of potash with ordinary printers’ ink, which, on being applied to albu- menized paper and exposed to light, become insoluble in turpentine, just the condition required. Other engagements have prevented us from following out the experiment to further practical results. But we mention the fact for the benefit of other experimentalists. We have already occupied more space than we intended but we shall probably, on another occasion, make another extract from this interesting pamphlet. — JOTTINGS FROM THE NOTE-BOOK OF A " PHOTOGRAPHER’S ASSISTANT.” No. I.—The Importance of PHOTOGRAPHY. Notwithstanding the many and continued efforts put forth by photographers, in order that the capabilities of their art may be fully developed, the vast improvements which
