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June 12, 1863.] THE PHOTOGRAPHIC NEWS. 281 sulphite of soda will be found the best fixing agent; while for the others to be mentioned cyanide is to be preferred, as leaving the deposit in a better condition for the after appli cations. The ordinary sulphate of iron developer, with the addition of citric acid, has been recommended as a convenient inten sifier. That it is clean, and works evenly and steadily, cannot be denied, but I think it is objectionable on account of the colour it produces—grey.- It is, in fact, density by deposit instead of by colour, and is therefore to be avoided. The application of a solution of iodine to the film before in tensifying with pyrogallic acid has also been advised, and, Where the original deposit is very thin, is undoubtedly use- fulthe more so as it slightly changes the colour. . The only important process now remaining to be discussed is that with bichloride of mercury and iodide of potassium. This comes into the third stage mentioned at starting; as to do any good the film must have been dried before the appli cation of the solutions. As a preliminary remark, I may say that it is judicious to varnish the edges of the plates to be operated on by this process, before the solutions are ap plied. The fact of having made a few hundreds of experiments tends to give me boldness when speaking of this process, and I have no hesitation in offering my opinion: that in careful hands it is capable of producing better results than any other; but I cannot recommend it for general use for various reasons. In the first place, if the exposure be not right to a second, no care or “ dodging ” will make a fine negative; and we all know—at least, all engaged profes sionally—that we cannot always take a second picture, while some irascible old gentleman, who wants to catch the “ next train,” is waiting to sit, and working himself into a state “better imagined than described,” by way of securing a pleasant expression. Then the printing from the nega tive requires extra care, another commodity, by the way, not always obtainable—and so on throughout. But, if prepared to give unlimited care, time, and atten tion to every part of the work, by all means use this process for the production of your negatives. Perhaps the most usual cause of failure in this process is the use of too strong a solution of bichloride of mercury. If, instead of a saturated solution, as usually recommended, we use one of from half a grain to a grain to the ounce of water, far better results will be obtained, and much of the unequal action so often complained of be avoided. The iodide of potassium solution of five grains to the ounce of water will be found to answer perfectly. It is a point of vital importance to the success of this process that there should be no deposit whatever on the deepest shadows. For the other methods named, this may not be so important, although it is best at all times, but it will be found useless to attempt to intensify by this method anything but the most brilliant and perfect pictures. Too great a heat should not be applied to pictures produced by this process while varnishing them, as some varnishes very readily dissolve the thin deposit of iodide of mercury formed upon the surface of the plate, leaving it in precisely the same condition as before intensifying. Chloride of gold has been recommended as an intensifying agent; but, beyond the objection of expense, it has that of being almost useless. Hyposulphite of soda, in conjunction with bichloride of mercury, has been spoken of as useful, as also hydrosulphate of ammonia; but, on the whole, none psthese substances can be favourably spoken of, the last . eng specially objectionable. A somewhat dangerous, yet a useful “ dodge,” when a negative is slightly over-exposed, is o pour over it a weak solution of iodine, and then, after 1oroug i washing, a weak solution of cyanide of potassium, rePed in o re process until some one or two portions of the deepest shadows are reduced to bare glass. For positives this answers capitally, if carefully executed; and, although 1 ( q.notrezammendit, a negative may frequently be saved byi must 110 ;ntfcour i* ter this treatment, the nega tive must be intensified by one of the before-mentioned processes—that with the bichloride of mercury having, in my hands, answered best. In concluding what I fear has been a very tedious paper, I would observe that in aiming, as we all do, at the produc tion of brilliant and perfect proofs, it must be kept in mind that all the parts of the process depend one on the other, and that perfection will only be attained when they are perfectly related one to the other. We are frequently astonished to hear of the most exquisite results being pro duced by means of a process which we thought incapable of producing them, and, on inquiry we find that the secret is simply this: the great care bestowed in arranging all the details, in order that one may work into the other. Then the importance of the arrangement of light on the model cannot be over estimated, lying, as it does, at the root of the question of intensity ; and it will be useless to work up processes for the production of perfect negatives, unless proper attention be paid to this. I had intended to commence this paper with some remarks bearing on this part of the subject, but, having a wholesome fear of Mr. Wall before me, I determined to leave that to him; as I do also the responsibility which might attach itself to me on account of having taken up your time this evening, for had it not been for his kindness in dragging me out on account of a few remarks which I made to him at the last meeting, I should not have ventured to occupy your valuable time this evening. I regret that through pressure o business I am unable to make this paper more perfect. Many experiments intended I have been unable to perform; but I have laid before you what is done, in the hope of resuming the subject at a future time. ART IN PHOTOGRAPHY. BY M. BLANQUaRr EVEARD. We know how little is due to art in the production of a photographic negative. The selection of the subject, the lighting of the model, and the pose, when’it is a living sub ject. This is but little, yet it is all to which the influence of art is reduced ; and still, little as it is, it is easy to recognise it in the pictures of operators who have a true perception and feeling for art, while we often have to regret its absence in those operators who owe all their success to science and skill in manipulation. Thus amid the magnificent progress imparted daily by science to photography, how much regret we experience that art remains as it was at its debut—powerless to modify, by taste or feeling, the picture proceeding from the Daguerrian camera. Let us conceive what a transformation photography would undergo if the operator would but regard the picture drawn in the camera by light only as a beautiful, faithful sketch waiting artistic inspiration to be completed. It would be like those rare engravings which, beside faithfully reproducing the work of the painter, bear also the impress of the individual feeling of the engraver, and render the copy superior to the original: The problem to be solved will then be to limit the marvellous but intelligent work of the camera to the complete but not intense formation of the image, and giving the photographer the means of continuing it, and modifying at will the aspect and accessories, and substituting, so to speak, his action for. that of the camera, and employing the same chemical means of execution. It is not a galvanic action like that we were the first to indicate in 1851, and which consists in precipitating by means of a metallic bath upon the image ready formed, but recognised as too weak, a fresh quantity of metal to strengthen it: This process, in daily use, can, fortunately, be performed only upon the whole surface of the negative; its result does not solve our problem as it does not modify the effects of the picture, it only changes the scale. Nor will it consist of the re-touches which a skilful hand is sometimes obliged to add to a negative. What pencil is skilful enough to combine its work with that performed by the luminous rays ? and yet