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121 Uhe Photographit Elchs, Lurc 12, 1880, PHOTOGRAPH! IN AND OUT OF THE STUDIO Printing by Development—Trying it on—The Radio graph. Printing by Development.—It, seems that the process in dicated by Captain Abney is one well worthy of a trial, and probably it will bo worked out to a successful and practical issue, if only a few of those who should be interested in its success will but put their shoulders to the wheel. In some experiments of our own with the process we have kept to the formula he has given, and we find that the results are everything that can be desired, except, perhaps, a slight loss of brilliancy, due to the sinking into the paper of the image. Slow development, as Captain Abney states, however, pre vents this in a very great measure, and we suppose that the theoretical reasons he has given will account for it. Our object in writing on this topic at all is, how ever, not to discuss the merits of the process, but, suppos ing it to be all we can wish, to look at the possibilities arising from it, A quarter-plate negative and a magic lantern are all that will be necessary to give us a print of any size we may require, and if any one possesses a nine- inch condenser, and a suitable lens, a whole plate may give us enlargements such as at present are most feasibly pro duced by the solar camera, as so successfully worked by Van Monckhoven, and our own countryman Mr. Viles in his microscopic enlargements. Possessors of even larger sized negatives need not despair when we remember that mon ster condensers, such as are possessed by the Autotype Company, can be purchased. The production of large direct negatives, as a 'rule, means cumbersome apparatus, heavy loads, and a smaller percentage of good results than when the photographic paraphernalia arc of the coat-pocket or knapsack size. As we have often pointed out in these columns, the desiderata for successful and comfortable photographic work are perfect small negatives, and a perfect enlarging process. The former can be obtained more easily than if the size is even confined to 9 by 7 plates. Have we at last the perfect enlarging process for printing by development ? We are all familiar with the gems of pictures which certain of our artists exhibit at our annual Exhibition. Their balance and rendering are perfect on the small scale on which they are printed, and yet only full justice can be done them if they are seen of a still larger size. Have wo now the possibility ? It will be in the recollection of our readers that Mr. Valentine Blanchard, some few years ago, showed to the Photo graphic Society the practicability of obtaining large paper negatives from enlarged transparencies by simply printing the latter on plain or albumenized paper, and after fixing the prints, rendering them transparent in the ordinary manner. In this case the production of a large print meant the use of a large camera, or, at all events, of a large glass, to produce the transparencies. The new method entirely dispenses with this, besides which, an enlarged print, taken direct from the small negative, should be superior to one in which it is produced from an enlarged paper negative taken after three distinct operations. Trying it on.—A gentleman, who is well known to the photographic world, lately poured out a grievance to us, and the grievance consisted in an attempt having been made to “interview” him. It appears that there are certain new applications of photography which he is experimenting on, and one day last week he was caught on the scene of his operations by a well-dressed being who began to insist on seeing what he was about. Our friend was very indignant, and demanded his name and occupa tion. Name j occupation, reporter!!! 11 1 thought,” said he, “ perhaps you’d like a few paragraphs about your self in different papers, and so on.” Boiling over, our friend replied, that when he wanted puffs he always did his own, and wished him good-day. Well, we sympathise with our acquaintance a good deal, as it was not for our “ At Home ” that the interview was sought; but he is a little bit too particular, to our mind. We once had a similar rencontre, and we were so civil; but it very funnily resulted in the paragraphs describing gelatine as collodion, and some other absurdities, which, of course, we quickly contradicted ; and thus we did in truth write our own puffs, much to the satisfac tion of every one except the reporting chap. Rather hard on him, perhaps, though we guess it served him right. He has not been to see us any more. Perhaps he has turned his attention to happier hunting grounds, where pyroxylin and collodion are not the hares to chase. The Radiograph.—One of the newest, and let us say one of the best, instruments that has lately been designed, has for its author a gentleman who was formerly well known in the columns of the Photographic News, Mr. D. Winstanley ; and as it is an instrument which is indirectly photographic, perhaps it is worthy of the attention of our readers. The radiograph is intended to measure, quantitatively, the intensity of the sun’s and sky’s heat throughout the day, and perhaps longer still. At a meeting of the Philosophical Society of Manchester, Mr. Winstanley read a paper in which he describes it to a certain extent. The instrument is essentially a diffe rential air-thermometer. There are two glass bulbs connected together by means of a bent tube, the bend being downwards, and where the bend is, there is intro duced a column of mercury, which, when each bulb is equally warm, lies exactly central. The apparatus is balanced on a knife edge, and if one bulb is slightly warmer than the other, the mercury shifts along the tube, disturbing the equilibrium of the apparatus, but the balance is recovered by one bulb slightly falling from the level. Attached to the bulb is a wire which rubs against a smoke-black paper attached to a cylinder rotating by clock-work once every twenty- four hours. The track of the wire shows the extent to which the bulb rises and falls. One of the bulbs is blackened with lamp-black, and the other silvered, so that after the normal temperature of the air has been taken up, any heat from the sky or sun will have much greater effect on the one than on the other. We have seen some of the records of sunshine in such blackened strips, and very remarkable they are : every passing cloud leaves its track by showing depression, whilst before sunrise the heat reflected by the sky is clearly indicated. Sunshine, as a rule, means actinism, and by-and-bye, no doubt, the photographer who keeps a diary will add this simple instrument to his stock-in-trade, and keep the records of sunshine in as complete a manner as he does his accounts. This seems to us a decided improvement on the plan for registering sunshine instituted by Mr. Campbell, and which is at present at work at the Kew and Greenwich Ob servatories, and from which the records of sunshine which appear in the daily papers are taken. In the early form of the instrument, sunshine was indicated by the charring action of the sun’s heat was focussed by a glass ball on to hemispherical bowls, such bowls being changed once every six months. In the newer form, the charring of strips of yellow card or black paper placed in a hemispherical ring indicates the amount of sunshine during each day, such strips being replaced daily. Com paring Mr. Winstanley’s instrument with either of these, we have a decided advance, since the former gives an indication of the comparative amount of heat in sun shine, whilst the latter tells us only that there has been sunshine at certain hours in the day, but tells us nothing else.