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272 state of knowledge respecting reduction, very little is required to render this kind of review of the processes employed perfect. The writer has noticed all the good methods of reduction, easy to follow, and giving remarkable results. Still, however, we find that he has not sufficiently recommended strengthening with sulphate of iron; there fore, we will describe yet another method preferable to the old one, which consists in continuing the reduction by means of pyrogallic acid. The negative, as soon as possible after exposure, is developed by pouring on to it the sulphate as slowly as possible, without dividing or breaking up the stream. The surface must be covered with a light, but continuous layer, taking care to employ only a small quantity of the liquid, just sufficient to cover the plate with a slight excess. If the operator contracts the habit of pouring on the iron solution veiy slowly he may reckon upon a diminution of the time of exposure equal to one-fifth of the whole. The negative is slightly washed, then covered with a solution of nitrate of silver of the strength of 2 to 3 per cent: the operation is performed in the same way as collodionizing a plate. The excess is collected, then the iron solution is again poured on in the same way as described for the silver solution. If, after this second operation, the negative is not completed, we proceed to a third, and even to a fourth, until ,it attains the desired vigour. It will be remarked that the negative being of a grey colour will not appear so opaque as those developed with pyrogallic acid. But this colour may be changed at the will of the operator by employing, in the last place, sulphate of iron with gallic acid, a bath which is rendered colourless by nitric acid. We may limit ourselves to passing the negative into a very weak solution of bichloride of mercury. It has become the fashion of late to decry the use of this latter substance on account of its causing opacity in the picture and liability to fade, but five years’ experience have never shown us these objectionable results. Employed in a concentrated solution the bichloride acts in the same manner as a strong dose of pyrogallic acid in presence of nitrate of silver, by rendering the image opaque, but in a weak solution the bichloride blackens the image without being accom panied with this inconvenience. In fine, strengthening with the sulphate of iron indicated above, is made with rapidity and certainty. It gives better results with portraits than pyrogallic acid yields, and its employment is free from the risk of failure. The quantity of sulphate of iron composing the bath has little or no influence upon the final result when the quantity of acetic acid is in direct ratio with the sulphate. If it is from 5 to 10 per cent, there must be at least 2 to 4 per cent, of acetic acid. If the quantity of sulphate reaches 15 to 20 per cent, there must be 6 to 9 per cent, to produce the same effect. When the bath is employed several days in succession, it is preferable to add from 1 to 2 per cent, of acetic acid, in order to re-establish it from day to day in its primitive con dition. In the proportions of 1 per cent of sulphate to 2 per cent, of acetic acid, we obtain an iron bath very nearly the same in its action as pyrogallic acid. Some operators add a quantity of alcohol to the bath in order to equalize the difference of density between the liquids. Possibly, they may obtain a good result, but veins of a greasy aspect multiply upon the collodion film, the reduction becomes unequal, and failure is a very frequent consequence. In practice, the following maxims are of very great importance:— 1st. That a negative developed an hour after exposure has lost much of its sensibility. 2nd. That in pouring the sulphate on slowly we obtain a negative with an amount of exposure which would only have yielded a positive, if the liquid were in large quantity and poured on rapidly. 3rd. That when we cover the film with the solution of nitrate, we strengthen the picture more quickly and with less silver than if, at several repetitions, it had been added to a portion of the iron bath. 4th. That a very weak solution of bichloride absolutely presents no inconvenience. MR. CLARK AND PHOTOGRAPHY AS A FINE ART. Dear Sir,—-In the News of last week appears a paper read by Mr. W. D. Clark, before the Photographic Society of Scotland, entitled “ Photography as a Fine Art.” It seems to me that the effect of this paper, if uncontra dicted in regard to many of its details, would be to convey very erroneous ideas of the present position, and probable future, of photography. Not having the advantage of the personal acquaintance of the writer of this paper, and being quite unacquainted with his name, either as a photographer or a painter, I shall be excused from all animus in calling attention to some of his assertions. Mr. Clark commences by drawing attention to the in feriority of photography to painting. Having yet to learn that the opposite has been asserted by any writer of autho rity, it may be assumed that it is a controversy of Mr. Clark’s creation—a statement made in order to be denied. Photography and painting base their claims to support on entirely distinct grounds. They are the offspring of minds having totally different objects in view. I am inclined to think that, with Mr. Clark, familiarity has bred contempt; the fact of the enormous demand for photographs causing every shop to be filled with them. But let us for a moment suppose that one of these cartes de visite, of which Mr. Clark speaks so slightingly, required months of labour to produce, and could then only exist as one single picture, without the power of reproduction, I feel certain that in such a case it would be pronounced the masterpiece of the most inventive ago ever known. Mr. Clark invites comparison between photographs and paintings ; let us, therefore, examine a little into the ques tion. The most immediately lucrative branch, both of painting and photography, is portraiture, anil as there is just now a large demand, it is a matter worth consideration. Two exhibitions, one of photographs, and one of paintings, (the Royal Academy) have been opened this year within a few hundred yards of one another, and a very large number of persons must have visited both. I have most carefully analysed the manner of treatment employed by artists whose portrait paintings are now suspended in Trafalgar Square, and confess my strong belief that taking them, as a whole, neither the pose, accessories, nor yet the very point on which Mr. Clark relies most—the expression—are by any means equal to photographs of high class. Again, Mr. Clark exultingly declares that photographs have no power to “ tell a story or appeal to the feelings.” How then about Mr. Robinson’s “ Bringing Home the May ?” I defy any unprejudiced person to assert that there is not in this picture the most exquisite “ story” of rustic life, or to state it floes not appeal to the feelings in the strongest and most forcible manner. Again, Lady Hawarden’s studies arc direct contradictions of Mr. Clark. In another branch, let us take the pictures of moving life by Mr. England and Mr. Breese. Surely that person must be wanting in every sentiment of beauty who can assert that these do not illus trate, in a manner never before dreamed of, the writings of poets in all ages. Few, very few, I am convinced, can look on these magical views of cloud, sea, and sunshine, without recalling our national “ Rule Britannia,” and an exclama tion of delight at the exquisite beauty of the result. Painters may colour their brightest, and pre-Raphaelites may draw each blade of grass and every leaf with painful correctness, but I cannot allow that these photographs are produced by any other than a high feeling of reverence for the beauties of