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July 27, 1883.] THE PHOTOGRAPHIC NEWS 467 ment in every-day photography. The other point is, that although the beneficial action of staining may be appreci ated in the case of the colours of the spectrum, which are pure and constant, it is very different with our pigments, I which are impure and inconstant. The region of the red and orange in the spectrum is one thing, and that produced, say, by vermilion or the chromes is another. Thus, there are blues we meet with every day that are rendered almost white in photography ; while others—the Prussian blue, for instance—come out dark in the photographic print, and are not incorrectly rendered by the camera in respect to light and shade. This fact must always be borne in mind by the photographer; he can never absolutely predict what shade a coloured fabric will appear in a photograph, although he knows very well that most blues come out light, and most yellows come out dark. Pigments, whether they are aniline dyes or body colours, are very different in their action to the pure tints of the spectrum. We are led to make these observations by reason of an article that has recently appeared in La Nature. Our con temporary publishes two diagrams which we reproduce, and which are supposed to prove beyond cavil the excellence for studio work of certain dry plates manufactured by a Paris firm. The plates are stained with eosine, and as a conse quence, we are assured, their capacity for reproducing colours at their proper value in respect to light and shade is very marked. Mr. J. R. Sawyer, in a recent paper read before the Photographic Society of Great Britain, put this matter of reproduction by photography in a very clear light. What is wanted, said Mr. Sawyer, is for photography to act the part of engraver, and translate the colours of an object into light and shade, which, to the eye, produce an effect similar to that of the original. This, we are led to infer, these special bromide plates, stained with eosine, and manu factured in Paris, enable the photographer to do. The left hand wood-cut shows certain colours as depicted by the ordin ary gelatine plate, the right-hand one the same colours depicted by an eosine gelatine plate. In the eosine plate it will be seen that the yellow is depicted light, and the blue dark, and there is that contrast between the two which in most cases it is desirable to acquire in photography. But it must be borne in mind, it is only a wood-cut we are looking at, and not a photographic print. As we have just said, there is little doubt that staining with eosine will permit the photographic film better to appreciate certain colours in their proper light, but this fact only is true in regard to the colours of the spectrum. Very possibly, too, eosine may also have a beneficial effect in the translating of certain pigments; but, at any rate, not to the extent these diagrams would lead us to believe. We fear the results are very much exaggerated. In any case, our readers may easily make the experiment forthemselves. Eosine is comparatively cheap. It may be purchased at any wholesale druggist—say, Burgoyne’s or Hopkin and Williams—at about fifteenpence an ounce, and this amount would suffice to stain many gross of plates. Eosine—which, by the way, is a bromine compound—dis solves readidy in water, and a cherry-red solution would be suitable for experiment. For ourselves, we have found that staining with eosine certainly has a tendency to reproduce certain blues of a darker tint, while yellow—we essayed a picture of ordinary yellow tammy—-appears to be rendered lighter than with the unstained film. But the results we obtained were too insignificant to be of any practical value. THE TOURIST PHOTOGRAPHER. Over the Stelvio Pass. The Stelvio has much to recommend it as an enjoyable tour. It is the highest pass in Europe available for carriages, it represents a most stupendous bit of road engineering, and finally it traverses one of the grandest mountain districts on the Continent. The way lies under the very shoulder of the snowy Ortler, the highest peak in the Tyrol, and in close proximity to the Bernina, an ice-crusted range, as mighty almost as that of Mont Blanc. A track that leads the traveller a thousand feet above the line of perpetual snow—for the top of the Stelvio is 9,000 feet—must needs bling before him new and varied scenes, not the least strik ing of which is the Monte Crystallo glacier, a smooth mass of gleaming white, like the icing of a gigantic bride-cake, that sweeps down to within a few yards of the road. The Stelvio leads from Italy into Austria. Coming from