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LMAY 7, 1869. comes in contact with it but the solutions and blotting- paper ; there is, therefore, no wonder that cleaner negatives are taken by this than any other means. By the bye, this reminds me of another “ grand part of the whole affair Can pictures be developed by dipping? For this is the point upon which the whole thing turns. It is the question of questions. In my opinion, it is the most im portant one that can be broached in connection with photo graphy. It is one that should be discussed in every photo graphic society. If answered in the negative, we must still go on with the “pouring on ” or “dark-room system,” with all its miseries and evils. “ Talented men " must continue to “ die in their prime,” and “ bright youths ” must become “ prematuraly old there will be no help for it. But, on the other hand, if answered in the affirmative, we may “ leave the beaten track,” and “ step from darkness into light.” On my own part, however, this question has no interest, for I have already solved it—solved it in the only way it or any other question can be solved, by experiment. I have experimented in everypossible way, and my answer is, yes, and better than by any other way—that is, if you use my protector. I affirmatively settled the question years and years ago, and I have ever since practised it. If it had not been so, my photo-camera-lucida would not have bee made, nor this article written. I cannot help expressing my surprise that photographers know so little about it. I was told by one years ago that it “could not be done,” and I was told so yesterday. “ Could not be done !” Why, I am sick of the words. Let them try, and, my word for it, they will find that it not only can be done, but better so than by any other way. It is just in this way. When I began my experi ments, I was told that if you immersed a sensitized collo dion plate wet with free nitrate of silver in a vessel (say an upright bath) containing a reducing agent, the silver would be thrown down to the bottom of the bath. I doubted it (the latter part of it), but I tried the experiment, and found that it was so with an unexposed plate, but with an exposed plate the case was different. When the plate was exposed to diffused light, the silver did not fall to the bottom, but was reduced all over the plate; but if a plate was ex posed behind a lens, as we do when taking a picture, certain portions only of the plate would be acted on by the light, and the silver would be reduced only on those por tions, and as no more silver could be reduced than was present, you could not over-develop, keep the plate in as long as you might. This settled the question. You can over intensify, but not over-develop. This is my principle, and on it I take my stand. When developing a plate in a dipping-bath by the aid of my protector, the circumstances are most favourable for the production ol a clean picture. The plate and the developing solution are, to a great extent, excluded from the air, and both are in total darkness, a condition of things to which I attach great importance, and there is, therefore, nothing to produce stains or marks of any kind, and there is no difficulty about the thing, or chance of a bad result, if you do not withdraw the plate too soon, and have given the right exposure. The developing solution can be used over and over again, and if you are working in a room (a light one, of course,) and are using one of my well-bottom- baths, holding halt a gallon of solution, you may develop hundreds of plates with it, and when its power is exhausted there will probably be some reduced silver from the back of the glasses, which may be put aside for residues. Inten sifying and fixing may also be done in the light—in baths, if you like—and thus this “ light room ” system may be, in every way, looked upon as one of economy and comfort I will now, Mr. Editor, bring this article to a close, which I fear is already too long. Not that I have exhausted my subject; indeed, I have not done anything like justice to it; but 1 will recur to it on a future occasion, if you think it of sufficient interest to your readers. There is one other point, however, to which I must refer before I close. By the interesting and important experiments upon the action of bromides in collodion, which have been carried on by Mr. Blanchard, a gentleman whose reputation as a practical and scientific photographer is well known to the photographic world, it would appear (as was stated by him at the South London Society on a recent Thursday evening) that by the addition of a certain amount of those salts, the sensitiveness of collodion would be so considerably increased as to require a proportionately increased strength of silver bath and developer to work in harmony with it; but—-and this is the point to which I am referring—the subdued and non-actinic light of dark rooms, or tents, was much too strong for these extremely sensitive chemicals, for you could not get the developer to flow on quick enough to prevent fogging the plate ; or, in other words, unless yon worked in the dark (which, of course, you could not do) these extremely sensitive chemicals are no use. Your readers will, no doubt, anticipate me in what I am going to say : my “ protector and baths ” are exactly the things to do it by, for, at the same time that the operator is work- in full daylight, the plate and the chemicals are in the total darkness required. Our scientific chemists may now go on with their researches for a more exalted class of chemicals than those at present in use (I mean in regard to sensitiveness) without any fear of their labour being in vain, and we may expect that the time is not far distant when we shall be enabled to photo graph badly-lighted subjects with a short exposure, and better-lighted ones instantaneously, a consummation devoutly to be wished. We now see that the “photo-camera-lucida,” with my “ plan of working,” is the very thing for the “ wet collodion process,” at home and abroad. But as the photographic world will, perhaps, object that it is hampered by protection, I will, in conclusion, observe, that having devoted so much time, labour, and money in its production, and seeing that by its adoption so large an amount of good will be effected as I have so feebly endeavoured to pourtray, I think they ought not to grudge me some little return for my labour’s.— I am, dear sir, yours obediently, Wm. WHITING. 26, St. Augustine's Road, Camden Square, N.W., April \bth, 1869. ENLARGEMENT OF SMALL LANDSCAPE NEGA TIVES BY THE SOLAR CAMERA* BY JOHN C. BROWNE. It has long been the desire of amateur photographers to make small landscape negatives in the field, and, after having returned from the expedition, to have solar enlarge ments made upon paper of various sizes, obviating the necessity of carrying large cameras and bulky apparatus when travelling for pleasure. Formerly, it was impossible to depend upon such an arrangement, as the prints were very deficient in sharpness; but, recently, improvements have been made in solar cameras and photographic lenses, which give a result but little inferior to contact printing. It is of the greatest importance that the negatives for enlargement should be first-class, of medium intensity, perfect sharpness, and fine detail. It must also be remem bered that slight defects, such as would scarcely be noticed in contact printing, are much increased by an enlargement of ten or twenty times the original size. That there is a prejudice against solar enlargements cannot be denied ; but much of the complaint at the present time has originated by photographers furnishing negatives for enlargement entirely unsuitable for the purpose, not giving a good contact picture in a printing-frame. No apparatus can ever be made to give satisfactory results from such negatives. Although not desiring to enter into a discussion as to which is the best form of solar camera, it is but justice to I * Read before the Photographic Society of Philadelphia.
