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120 THE PHOTOGRAPHIC NEWS. [MARCH 6,1863. Ualk in the Studio. Double Sulphate OF Ikon and Ammonia.—This double salt recently recommended by M. Meynier as a developer in preference to the ordinary protosulphate of iron has been manufactured by Messrs. Horne and Thornthwaite. We find on trial that it has certain advantages. Using a 25-grain solu tion with 25 minims of acetic acid it gave very good results. The action was very regular and perfectly under control, giving greater density and cleaner shadows than a similar solution of the usual protosulphate. This is what we anticipated, as the general presence of a large portion of sulphuric acid in the common pro- tosulphateofirontendstotheproductionofathin greyimage, with slightly veiled shadows, and this in the double salt is avoided. M. Davanne expresses a conviction that with this latter the mole cules are thrown down in a much finer state of subdivision than with the ordinary developer, thus securing a more delicate image. The double salt is also more stable, having less tendency to peroxidation. Paisley Photographic Society.—We are glad to see from a local paper that a photographic society is in active operation in Paisley. A meeting was held on Thursday evening week, Mr. Robert Harris, Vice President, in the chair. The subject of the evening was recent improvements in toning processes. Amongst other things exhibited was a very beautiful print, taken from a negative photographed by Mr. Edmonds, from Mr. Stewart’s fine painting of “ Interrupted Studies,” at pre sent in the Edinburgh Exhibition, and Mr. Archibald Barr also exhibited some fine prints on the newly introduced tinted paper. Mr. John Clark, Gateside, presented to the society’s library a handsome bound volume of the Photographic News for 1862, in consideration of which, and also of the many valuable dona tions he has repeatedly presented to the society, they awarded him a cordial vote of thanks, and instructed the Secretary to transmit him the same. A vote of thanks to the Chairman terminated the proceedings. Ammonia Development.—Speaking of the ammonia deve lopment, Major Russell says :—“ In certainty, this method, as I now manage it, leaves nothing to be desired, and there seems to be less liability to stains, or spots, than in the acid method. The only points which I have lately found out are, that com mercial carbonate of ammonia is a little better than the solution of ammonia, and that the best proportion is 1 grain to 1$ grain of the carbonate to 1 grain of pyrogallic, to be used in from 2 drachms to 1 ounce of mixed developer. Within these limits' there is little difference in the effect; the stronger the developer the quicker its action, but the weaker the more entirely free from all veiling will be the negative: the amount of detail brought out does not seem to be affected by the degree of dilution within the limits mentioned. The best way is to pour the ammonia, dissolved in equal parts of alcohol and water, over the dry plate, then to mix the pyrogallic, and pour on again.” A new edition of Major Russell’s little work, “ On the Tannin Process,” will shortly be published. We have just received an interesting letter from Mr. Leahy, on the develop ment of dry plates, in which he says lime-water will develop tannin negatives. The letter in our next. U0 Gortespoudents. A. Lewis.—Your “spirit photograph” is much more spiritual looking than the alleged genuine pictures produced in America, which arc very clumsily managed. The ghostly effect in your attempt is very well managed. Bromide.—The arrangement of canopy or screens in taking portraits in the open air must depend largely on circumstances. The canopy may be made of the slate-coloured glazed calico to which you refer; the extent to which it should project forward over the head must depend much upon its heigh t or dis tance above the head. The light should reach the head at about an angle of 45°, so that a canopy a yard and a half above the head should project about a yard and a half over it. There need not be a screen or wall on both sides necessarily ; but if you have a wall on one side you will find a screen of three or four feet wide, and about as many feet from the sitter on the other side will help you to get softness, and prevent too much light falling quite on the side of the face. To prevent diffused light entering your lens, attach to it a large conical hood of cardboard blackened inside, and projecting about a foot, in size and shape something similar to a sugar loaf, but expanding a little more. A Man from the Country.—The stain on the background of your negative appears to have arisen from an accumulation of the silver solution having drained to that spot, and become precipitated there by the developer. Try placing a strip of blotting paper along the bottom of the plate, which will absorb any surplus drawings. We have met with the tendency as you des cribe in a new bath, and there is something not explained in the circum- stance that it should occur especially in a new bath ; but we think you will find the remedy efficient. The general chemical quality of your nega tives appears pretty good. Report on your glass in our next. •lotographs Registered during the Past @@Reekt. Messrs. W. and D. Downey, 9, Eldon Square, Newcastle-on-Tyne, Two Portraits of John Bright, Esq., M.P. Portrait of George Dawson, Esq. Mr. John Stuart, Glasgow, Two Photographs of Rev. Niel Brodie. Mr. Brothers, Manchester, Portrait of late Rev. W. J. Ffarrington. Two Portraits of Rev. J. Atkinson Longsight. Portrait of Rev Canon Richson. Messrs. C. A. Du Val and Co., Manchester, Photograph of Colonel Greathed. „ of Earl of Derby. Mr. Theophilus Smith, Sheflield, Two Portraits of John Brown, Esq., Mayor of Sheffield. Mr. E. T. Brooks, Newbury, Bucks, Portrait of the Rev. the Warden of All Souls. „ of Archdeacon Ffoulkes. „ of Rev. T. T. Carter. » of Rev. T. V. Fosbury. J. Jones.—We do not necessarily indorse or approve all the formulas we publish, and amongst other things we do not recommend or practise our selves, is the adding of alcohol to the nitrate bath. The ammonia nitrate bath with nitric acid added until it is neutral gives exceedingly good results. Let any turbidity subside, or if necessary, filter the solution. Alpha.—We think the lenses of the best English makers are decidedly pre ferable to the common French articles. The superiority consists in a variety of points, such as better definition thoughout, greater rapidity, &c. We cannot, in fairness, recommend any maker by name. See our advertise ment columns. Thompson.—The sei (Por toning bath is a mixture of hyposulphite of soda and gold. Dissolve one grain of chloride of gold in an ounce of water; in another ounce of water dissolve three grains of hyposulphite of soda ; now pour the gold solution in the hypo solution, agitating it during the process. Dilute with a couple of ounces of water, and when any turbidity or milkiness has subsided, filter, and it is ready for use. This process is now rarely used, as it has been abandoned for the alkaline gold process, which gives better and safer results. G. II. M. — Fresh glasses generally need no other cleaning agent but alcohol and tripoli. Glasses that have been used should be cleaned with the same, with the addition of a little nitric acid; a little iodine may also be added with advantage ; finishing with alcohol alone. If the plates are well cleaned, and the edges carefully rubbed to remove adhering parti cles, there is no danger of the bath suffering. A Tanner.—About four grains of the iodide of magnesia, and one or one and a half of bromide of magnesia, may be; used with advantage in each ounce of collodion. 2. It is desirable to evaporate the nitro-muriatic acid as closely as possible, without inducing decomposition, but it is necessary to be very careful towards the close of the operation, and work with a low temperature, or decomposition may suddenly take place. J. B.—See article on "Glass Houses,” in the present Number. A modifica tion of Mr. Sutton’s principle—getting a little more light—will probably suit you better than the design with top light only. F. Treble.—A combination of softness and delicacy with brilliancy is neces sary to good results. In the cards sent, No. 1 is the most perfect negative, but it is not a good print, being too lightly printed. A little more printing would have given depth and richness to the drapery, and more roundness and modelling to the features. No. 2 is brilliant, but a little hard ; a trifle more exposure, and less developing or intensifying, would have improved the picture. No. 3 is better in these respects; but it errs a little on the side of softness : it wants a little force. A medium between No. 2 and No. 3, or a combination of some of the qualities of both would give a fine result. If you examine the face of No. 2, you will find patches of white without any detail or drawing, which should never occur, and no richness or perfection of the drapery will compensate for this. W. C„ Market Rasen.—A longer immersion in the toning bath will give you deeper and blacker tones; but the highly albumenizedRive paper on which your print is produced is often difficult to get beyond the chesnut tone of your specimen, a tone which, however, many persons prefer. A few lessons from a capable instructor will be valuable; but we do not know anything of the qualifications of the gentleman to whom you refer. Alex. Arnstein.—Thank you for the samples of paper prepared with gutta percha, we will take an early opportunity of trying it. One who Wants Practice.—The print received is a specimen of imperfect fixation. The hyposulphite bath is too weak, or old and exhausted, or the prints have stuck together so that the solution did not act properly upon all. In this case the latter is probably the fact, as you state that some of the same batch were so and some perfect. The effect generally is first seen whilst the prints are washing. Prints perfectly washed before toning or after toning are much less liable to this mischance. There are no means of aseertaining when a print is fixed by its appearance. The only certainty can be obtained by taking care to observe all necessary precau- tions, such as careful washing, using fresh, strong, neutral hypo solution, keeping the prints in motion and free from sticking together, &c. George Draper. —We did not find any print enclosed in your letter. Possibly a little alcohol will prevent the stains to which you refer ; or possibly they may arise from the drainings of the plate ; we tell from your description. 2. You may, without impropriety, defer intensifying until the close of the day, as is the custom with many artists. You may cither allow the negatives to dry, or keep them in water just as you prefer; with the latter plan there is some chance at times of the film becoming loose. F. L. S., Edge Hill.—The chief fault of your pictures is the use of too much front light, giving the faces a uniform and flat effect, you want more dis tinctly marked light and shadow to give more relief. A. Wood.—We are obliged by the examples of the effect of steaming; which seem strikingly to prove its value. We shall look with interest for Mr. Nichol’s paper on the subject. We should like to know something of your photolithographic process. We have not yet exposed the piece of excited paper, so that we shall learn something of its keeping powers. A. Burns.—The cards received ; we will write shortly. Y. Z.—Your sample of glass is very excellent, and may be used in the dark room with perfect safety.
